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SpaceX Vehicles and Missions => SpaceX General Section => Topic started by: Chris Bergin on 06/06/2019 08:02 pm

Title: Starlink : General Discussion - Thread 2
Post by: Chris Bergin on 06/06/2019 08:02 pm
For links to other Starlink discussion threads, launch threads, and FCC filings take a look at the Starlink Index Thread (https://forum.nasaspaceflight.com/index.php?topic=48981.0)



Thread 1:
https://forum.nasaspaceflight.com/index.php?topic=36552.0

Articles:
https://www.nasaspaceflight.com/?s=Starlink

-

Please don't clutter this thread with arguments about the "impact" for astronomers, etc.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 06/07/2019 05:13 pm
Moved a couple posts to make a new thread in the Commercial Spaceflight section for discussing the impacts on astronomy stuff:
Impacts of Large Satellite Constellations on Astronomy (https://forum.nasaspaceflight.com/index.php?topic=48302.0)

Most discussion on the impacts of satellite constellations on astronomy should go to the new thread.  Anything in this thread should be Starlink specific (such as SpaceX announcing mitigation measures specific to their satellites).
Title: Re: Starlink : General Discussion - Thread 2
Post by: oldAtlas_Eguy on 06/08/2019 08:02 pm
Do we have an estimate of when the 56 "good" sats will reach their "final" orbital positions? That plus a few months for tests and software tweaks would give us a a good estimate on when to expect the next launch of the V1.0 sats for which final design decisions to pick the best design options being tested by this current V0.9 smorgasbord designs for the best price performance design finalization. Although the next batch may be a reduced variation down design set it may not yet be the V1.0 "final".
Title: Re: Starlink : General Discussion - Thread 2
Post by: Lar on 06/09/2019 03:03 am
Or they may launch another bunch that don't necessarily incorporate everything hardwarewise that needs to change but still let them test. Getting several bunches in orbit in different phases of the process seems like good practice.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 06/09/2019 12:46 pm
Or they may launch another bunch that don't necessarily incorporate everything hardwarewise that needs to change but still let them test. Getting several bunches in orbit in different phases of the process seems like good practice.

It will be very interesting to see if they request any more deviations from their license on the next set or not.  Based on what they've filed to date they should start launching with Ka-band capability on the next full launch.
Title: Re: Starlink : General Discussion - Thread 2
Post by: su27k on 06/12/2019 03:49 am
Simulation showing the global coverage area of 6 and 12 orbital planes from early Starlink deployment:

https://www.youtube.com/watch?v=k73AFybi7zk
Title: Re: Starlink : General Discussion - Thread 2
Post by: su27k on 06/12/2019 03:52 am
Some tidbits from Tesla shareholder meeting:

https://twitter.com/jackiewattles/status/1138574349231886339
Quote
Musk just asked at Tesla shareholder meeting whether SpaceX's Starlink internet will reach cars.

His response: SpaceX probably has the most advanced phased array antenna in existence, including the military. But it's about the size of a pizza box. That would look weird on a car.

https://twitter.com/b0yle/status/1138574399890546688
Quote
Could @Tesla cars be equipped with #Starlink satellite antennas for internet connectivity? @elonmusk sounds doubtful. Pizza-size antenna would "look a little odd on the roof of a sedan." (1/3)

[email protected] says main value of #Starlink satellite constellation is to provide "low-latency, high-bandwidth access to relatively low-density areas" such as rural and semi-rural environments. (2/3)

#Starlink satellite service is "not ideal for high-density cities," @elonmusk says at @Tesla shareholder meeting. (3/3) cc: @SpaceX
Title: Re: Starlink : General Discussion - Thread 2
Post by: psionedge on 06/12/2019 07:34 am
So now the key market is people that could buy service from HNS and Viasat?

I thought the low-latency was the key to unlocking big money in HFT markets.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Robotbeat on 06/12/2019 12:46 pm
So now the key market is people that could buy service from HNS and Viasat?

I thought the low-latency was the key to unlocking big money in HFT markets.
The HFT telecon market is small. There’s not “big money” there. This idea was never mentioned by Elon or SpaceX, it’s just an internet thing.

Realize that HFT markets have dedicated point to point microwave links that for the most part can get even lower latency.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Zed_Noir on 06/12/2019 02:18 pm
Some tidbits from Tesla shareholder meeting:

https://twitter.com/jackiewattles/status/1138574349231886339
Quote
Musk just asked at Tesla shareholder meeting whether SpaceX's Starlink internet will reach cars.

His response: SpaceX probably has the most advanced phased array antenna in existence, including the military. But it's about the size of a pizza box. That would look weird on a car.

https://twitter.com/b0yle/status/1138574399890546688
Quote
Could @Tesla cars be equipped with #Starlink satellite antennas for internet connectivity? @elonmusk sounds doubtful. Pizza-size antenna would "look a little odd on the roof of a sedan." (1/3)

[email protected] says main value of #Starlink satellite constellation is to provide "low-latency, high-bandwidth access to relatively low-density areas" such as rural and semi-rural environments. (2/3)

#Starlink satellite service is "not ideal for high-density cities," @elonmusk says at @Tesla shareholder meeting. (3/3) cc: @SpaceX

Tesla could integrated the receiving antennas for Starlink to areas of the bodywork that isn't glass. Like the frunk lid, trunk lid, door panel, etc. on cars, SUVs & pickup trucks.

However mounting a pizza box size trainable antenna on the Tesla semi seem a lot more doable. Think most trucking companies wants internet connectivity with their trucks just for vehicle tracking alone.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Tulse on 06/12/2019 02:54 pm
However mounting a pizza box size trainable antenna on the Tesla semi seem a lot more doable. Think most trucking companies wants internet connectivity with their trucks just for vehicle tracking alone.
And I would think that semis are also far more likely to be out of range of cell data coverage than passenger vehicles are.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Marine_Mustang on 06/12/2019 03:06 pm
However mounting a pizza box size trainable antenna on the Tesla semi seem a lot more doable. Think most trucking companies wants internet connectivity with their trucks just for vehicle tracking alone.
One great application is for real-time, high-quality video from anywhere without the high fees associated with cellular data connections. Many trucking companies have installed multiple cameras on their truck fleets, including in the cab, and monitor those feeds for driver noncompliance with regulations and for instant review of footage when sensors indicate there has been a collision. I have family members that worked in that area; reviewing video in real-time or near real-time. Of course, there's also the need for vehicle location tracking, but other data that would be useful is telemetry for certain kinds of cargo; e.g. temperature of refrigerated trucks, monitoring of hazardous loads, etc.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Tulse on 06/12/2019 03:24 pm
And real-time monitoring of cargo trucks will become vital once autonomous driving becomes more commonplace.
Title: Re: Starlink : General Discussion - Thread 2
Post by: niwax on 06/12/2019 03:55 pm
While we're on this tangent, where Starlink really makes sense is for remote locations that need a solid data connections, like Superchargers. Not only do they need to be connected for billing, they are playing around with offering Wifi so the car can download updates and upload feedback while it charges.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Robotbeat on 06/12/2019 11:28 pm
And real-time monitoring of cargo trucks will become vital once autonomous driving becomes more commonplace.
Already a thing.
Title: Re: Starlink : General Discussion - Thread 2
Post by: AC in NC on 06/13/2019 03:23 am
And real-time monitoring of cargo trucks will become vital once autonomous driving becomes more commonplace.
Already a thing.

Likely not at the scale, granularity, and fidelity necessary given the potential adoption magnitude and liabilities?
Title: Re: Starlink : General Discussion - Thread 2
Post by: LiamS on 06/13/2019 01:14 pm
just doing some back of the napkin calculations, during the tesla earnings call said that they want starlink to serve 3-5% of the worlds population, using an arbitrary monthly price of $50 starlink would earn:

For 3%
11.3 B/month or 135.5 B/year

For 5%
18.8 B/month or 225.9 B/year

Thats a lot or revenue
Title: Re: Starlink : General Discussion - Thread 2
Post by: docmordrid on 06/13/2019 04:41 pm
>
For 3%
11.3 B/month or 135.5 B/year

For 5%
18.8 B/month or 225.9 B/year

Thats a lot or revenue


Mars Needs Women,...men, hardware, habitats, boring/drilling equipment, Tesla-M vehicles, reactors....and Musk could take Tesla private.
Title: Re: Starlink : General Discussion - Thread 2
Post by: oldAtlas_Eguy on 06/13/2019 08:16 pm
>
For 3%
11.3 B/month or 135.5 B/year

For 5%
18.8 B/month or 225.9 B/year

Thats a lot or revenue


Mars Needs Women,...men, hardware, habitats, boring/drilling equipment, Tesla-M vehicles, reactors....and Musk could take Tesla private.
Even if they only achieve .3% in 10 years that is still $13B to$23B.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Kragrathea on 06/14/2019 07:36 am
just doing some back of the napkin calculations, during the tesla earnings call said that they want starlink to serve 3-5% of the worlds population, using an arbitrary monthly price of $50 starlink would earn:

For 3%
11.3 B/month or 135.5 B/year

For 5%
18.8 B/month or 225.9 B/year

Thats a lot or revenue
The vast majority of those 3% could never afford $50 a month.  And I doubt they get more than %30 of any market.

I think a more realistic back of the napkin is this. They have filed with the FCC for 1mil base stations (presumably in the US). Lets assume they get $100-500 a month per (those base stations serve to 100s of users so 1-5$/mo/user). And $100m-500m/mo revenue for SpaceX from North America. About the same from Europe, presumably less from places like Africa where even $1 per user would be too much. 
Title: Re: Starlink : General Discussion - Thread 2
Post by: Kragrathea on 06/14/2019 07:47 am
I happened to be going through Montana and I stopped by the Starlink ground station near Conrad MT to take some pictures. It sits in the middle of a field a few miles out of a very small town. I thought maybe a fiber line ran nearby or something but as far as I can tell the only reason picked it was because of the lat/lon. And maybe a good view of the horizons.

Google maps location
https://goo.gl/maps/YkRVsRsnWUt71iwQA
Title: Re: Starlink : General Discussion - Thread 2
Post by: catdlr on 06/14/2019 08:07 am
Great initial posts, Kragrathea, welcome to the Forum. 

General question to anyone reading, the power and telemetry buildings seem to be able to stand up to the environment. I'm not too sure about the situation with the antennas on the flatbed.  Seems like they will get covered up by snow during the winter season.  Would they be better on some towers?
Title: Re: Starlink : General Discussion - Thread 2
Post by: JamesH65 on 06/14/2019 10:25 am
Great initial posts, Kragrathea, welcome to the Forum. 

General question to anyone reading, the power and telemetry buildings seem to be able to stand up to the environment. I'm not too sure about the situation with the antennas on the flatbed.  Seems like they will get covered up by snow during the winter season.  Would they be better on some towers?

Why on earth would you think that the final installation will be on flatbeds? This is prototype stuff, if they get covered with snow, they just brush it off.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 06/14/2019 01:43 pm
I think a more realistic back of the napkin is this. They have filed with the FCC for 1mil base stations (presumably in the US). Lets assume they get $100-500 a month per (those base stations serve to 100s of users so 1-5$/mo/user). And $100m-500m/mo revenue for SpaceX from North America. About the same from Europe, presumably less from places like Africa where even $1 per user would be too much.

Those 1M Ku-band base stations are for individual users/businesses/households.  They are different from the Ka-band gateways that will be handling large amounts of traffic.  The current Ku-band gateways are supposed to be temporary.  (I'd bet there are quite a few people in Africa who can afford more than $1/month for internet service, and many installations will probably be shared in small towns.)
Title: Re: Starlink : General Discussion - Thread 2
Post by: vsatman on 06/14/2019 04:45 pm
They have filed with the FCC for 1mil base stations (presumably in the US). Lets assume they get $100-500 a month per (those base stations serve to 100s of users so 1-5$/mo/user). And $100m-500m/mo revenue for SpaceX from North America. About the same from Europe, presumably less from places like Africa where even $1 per user would be too much.
Sorry but you cannot connect 100 users (= homes or families ) to one terminal  via wi-fi in rural territory...

One house = one family = one user terminal = 50 USD/month = average 550..570 USD/user per year (not forget about churn)
for 1 Mio user  is revenue 560..570 Mio USD per year  is good and real business !

Compare:  Hughes had in 2017 1,26 Mio users (total in USA,Canada, Mexico, Brazil etc)
minimal tariff plan 60 USD /mo ( max is 130 USD/mo ) and 1477 Mio USD total revenue in 2017 (consumer broadband + 200+ corporate networks + military + aviation broadband + hardware delivery to more then 100 Operator in all the world) ..
https://www.hughes.com/who-we-are/resources/press-releases/echostar-announces-fourth-quarter-and-full-year-2017-results
Title: Re: Starlink : General Discussion - Thread 2
Post by: cro-magnon gramps on 06/14/2019 05:00 pm
Anyone here, heard if Starlink has applied to the CRTC in Canada for authorization to sell the base stations in Canada? Presumably they would need to pass regulatory inspection for use? The Website for Starlink does mention that the first six launches would cover the USA AND Canada.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Kragrathea on 06/14/2019 08:12 pm
Sorry, I meant 100 users per in a situation like a base station with a cell tower attached like you would use in Africa.

Starlink isn't designed for one base station=one house hold. I'm not saying some people wont do that but that is not the intent. Again they have applied for 1 mil base stations in the US. That is 1 per 127 house holds. Or if they get to 3% 1 base = ~4 households.

Check me if I am wrong but phased array or not one sat can only look at so many base stations at a time before it becomes overwhelmed with signals. I think thats part of why Elon have said it isn't for urban areas. So they have to limit the total number of ground stations. And if it so cheap that everyone wants his own fast gigabit pipe to the sky they will have too many base stations to handle.  I expect it will _have_ to be priced high enough per base station to discourage one household per. 
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 06/14/2019 08:18 pm
Starlink isn't designed for one base station=one house hold. I'm not saying some people wont do that but that is not the intent. Again they have applied for 1 mil base stations in the US. That is 1 per 127 house holds. Or if they get to 3% 1 base = ~4 households.

Check me if I am wrong but phased array or not one sat can only look at so many base stations at a time before it becomes overwhelmed with signals. I think thats part of why Elon have said it isn't for urban areas. So they have to limit the total number of ground stations. And if it so cheap that everyone wants his own fast gigabit pipe to the sky they will have too many base stations to handle.  I expect it will _have_ to be priced high enough per base station to discourage one household per.

No.  It is designed for one antenna per household.  The 1M number is just a random round number to get started with, they have to ask for something in the license application.
Title: Re: Starlink : General Discussion - Thread 2
Post by: vsatman on 06/14/2019 08:25 pm
Anyone here, heard if Starlink has applied to the CRTC in Canada for authorization to sell the base stations in Canada? Presumably they would need to pass regulatory inspection for use? The Website for Starlink does mention that the first six launches would cover the USA AND Canada.
I mean  there are 2 different theme
1) Starlink`s satellites  will cover part of Canada territory near border with USA
2) Starlink  has to ask  Canadian Authority (=CRTC?) for right to use standart Ku Band frequency  11-14 GGz in Canada. But Canadian Satellite Operator Telesat (about 30% shares has Canada’s Public Sector Pension Investment Board )  has  13 own satellites on GSO, which use Ku band  and  plans for own LEO constelation  TeleSat LEO, (will use only Ka band) , but TeleSat LEO as constellation will compete with Starlink ..
Space X has to convince CRTC that Starlink`s constellation will not interrupt Telesat`s GSO Satellites ...
Title: Re: Starlink : General Discussion - Thread 2
Post by: ZChris13 on 06/14/2019 08:29 pm
Starlink isn't designed for one base station=one house hold. I'm not saying some people wont do that but that is not the intent. Again they have applied for 1 mil base stations in the US. That is 1 per 127 house holds. Or if they get to 3% 1 base = ~4 households.

Check me if I am wrong but phased array or not one sat can only look at so many base stations at a time before it becomes overwhelmed with signals. I think thats part of why Elon have said it isn't for urban areas. So they have to limit the total number of ground stations. And if it so cheap that everyone wants his own fast gigabit pipe to the sky they will have too many base stations to handle.  I expect it will _have_ to be priced high enough per base station to discourage one household per.
One household per is the only way to for it to work in rural America, where houses are separated by miles. There is for sure a market for shared ground stations elsewhere, but it's a function of housing density. Luckily both ends work as a function of density in a way that could cancel out, we'll see if there's any dead zones where it doesn't close, other than the densest urban areas, where data demand would exceed data supply, even if you split it up.
Title: Re: Starlink : General Discussion - Thread 2
Post by: vsatman on 06/14/2019 08:50 pm
I think thats part of why Elon have said it isn't for urban areas.
I see 3 reasons:
1) In cities mostly houses had  fiber today. Why  user will change existing provider??
2) In cities  in next 2-3 years will be built 4G/5G coverage and all owners mobile pnones or  notebooks automaticallywill have access to high speed internet  without any additionally devices and new contract with new company.
3) last but not least Starlink needs  direct view on satellites with angle 25+ degrees .. constantly and 360 degrees around. In Mahnhattan this is inpossible...
Title: Re: Starlink : General Discussion - Thread 2
Post by: ThomasGadd on 06/14/2019 08:52 pm
Anyone here, heard if Starlink has applied to the CRTC in Canada for authorization to sell the base stations in Canada? Presumably they would need to pass regulatory inspection for use? The Website for Starlink does mention that the first six launches would cover the USA AND Canada.
I mean  there are 2 different theme
1) Starlink`s satellites  will cover part of Canada territory near border with USA
2) Starlink  has to ask  Canadian Authority (=CRTC?) for right to use standart Ku Band frequency  11-14 GGz in Canada. But Canadian Satellite Operator Telesat (about 30% shares has Canada’s Public Sector Pension Investment Board )  has  13 own satellites on GSO, which use Ku band  and  plans for own LEO constelation  TeleSat LEO, (will use only Ka band) , but TeleSat LEO as constellation will compete with Starlink ..
Space X has to convince CRTC that Starlink`s constellation will not interrupt Telesat`s GSO Satellites ...

By design, Starlink will not transmit if a GSO satellite is within 22 degrees (earth to satellite).
Title: Re: Starlink : General Discussion - Thread 2
Post by: groundbound on 06/14/2019 09:14 pm

1) In cities mostly houses had  fiber today. Why  user will change existing provider??


Because we absolutely hate those providers. They have abused their monopoly position for decades. I personally would pay slightly more, for slightly worse service just to act out my built-up hatred.
Title: Re: Starlink : General Discussion - Thread 2
Post by: vsatman on 06/14/2019 09:46 pm
By design, Starlink will not transmit if a GSO satellite is within 22 degrees (earth to satellite).

What I found in Space X filing to FCC   SATMOD2018110800083, SpaceX NGSO Constellation.
work area is more as 25 degrees (see attached file)

but for Anic F2, Anic F3 or Anic G1  in Winnipeg , Ottawa or Montreal   have angles 27...29 degrees and interruption is theoretically possible

Title: Re: Starlink : General Discussion - Thread 2
Post by: ThomasGadd on 06/14/2019 11:38 pm
By design, Starlink will not transmit if a GSO satellite is within 22 degrees (earth to satellite).

What I found in Space X filing to FCC   SATMOD2018110800083, SpaceX NGSO Constellation.
work area is more as 25 degrees (see attached file)

but for Anic F2, Anic F3 or Anic G1  in Winnipeg , Ottawa or Montreal   have angles 27...29 degrees and interruption is theoretically possible

I'll look where I found that number but the important point is there is an existing method for dealing with GSO satellites.
Title: Re: Starlink : General Discussion - Thread 2
Post by: guckyfan on 06/15/2019 08:43 am
My understanding is that these are two different matters. One is the max angle sats are operating in relation to ground stations. The other is that they will not use angles close to the beam direction of a GEO satellite using the same frequency to avoid interference.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gtae07 on 06/15/2019 09:48 am

1) In cities mostly houses had  fiber today. Why  user will change existing provider??

Because we absolutely hate those providers. They have abused their monopoly position for decades. I personally would pay slightly more, for slightly worse service just to act out my built-up hatred.
THIS.

I'd bet I could get plenty of people in my subdivision (~250 houses) to go in together on a Starlink terminal just to give a middle finger to our local provider (our only choice for internet service besides 4G through a cell carrier).  We have no competition here and thus we pay 3-4x what everyone else does for comparable service.  Even people living out in the sticks get better service than we do, and we're a fairly new subdivision in a growing suburb.  Up until about two years ago we were paying $70 for 5 megabit service. 

Heck, I'd drop a grand or two myself on the hardware and get my own terminal if I could. 
Title: Re: Starlink : General Discussion - Thread 2
Post by: 2megs on 06/15/2019 12:23 pm
I'd bet I could get plenty of people in my subdivision (~250 houses) to go in together on a Starlink terminal just to give a middle finger to our local provider...

History suggests otherwise. When Google Fiber rolled out tremendously better service at low prices, they found way less uptake than they needed to make it viable. People just sort of shrugged and continued with whatever didn't require them to make changes or understand the difference between a kilobit and a gigabit.

We'd all make the switch in a heartbeat, but the kind of people who join an online forum to obsesses over the technical details of spacecraft aren't a representative sample of the general population. It seems most people would rather not worry about it.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Herb Schaltegger on 06/15/2019 03:40 pm
I'd bet I could get plenty of people in my subdivision (~250 houses) to go in together on a Starlink terminal just to give a middle finger to our local provider...

History suggests otherwise. When Google Fiber rolled out tremendously better service at low prices, they found way less uptake than they needed to make it viable. People just sort of shrugged and continued with whatever didn't require them to make changes or understand the difference between a kilobit and a gigabit.

We'd all make the switch in a heartbeat, but the kind of people who join an online forum to obsesses over the technical details of spacecraft aren't a representative sample of the general population. It seems most people would rather not worry about it.

There’s a lot more to the story of Google Fiber’s failure regarding uptake. In my general area (Nashville), the market competitors lobbied very hard and very effectively to prevent Google from gaining access to the same pole and underground easements that they already held exclusive leases to. Consequently, Google could only penetrate those very few areas undergoing extensive in-fill redevelopment (e.g., the Gulch area near downtown, which was formerly industrial use and railyard-adjacent warehouse districts), and a few newer developments in the smaller remaining green spaces. After attempts to batter their way through the local B.S. (funded mostly by Comcast) they basically gave up.

However, in the suburban areas outside Metropolitan Davidson County area, AT&T took advantage of their pre-existing POTS easements to run fiber as built out their network. My neighborhood of a couple hundred houses was fiber’ed up over the course of a couple months. My house was the first in the neighborhood - and quite possibly my entire city - to get fiber-to-the premises over 3 years ago.

The takeaway from this being, absent well-funded and effective local and state-wide lobbying efforts by competitors to prevent uptake, new technologies can certainly take off at the right price.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gtae07 on 06/15/2019 05:58 pm
I'd bet I could get plenty of people in my subdivision (~250 houses) to go in together on a Starlink terminal just to give a middle finger to our local provider...

History suggests otherwise. When Google Fiber rolled out tremendously better service at low prices, they found way less uptake than they needed to make it viable. People just sort of shrugged and continued with whatever didn't require them to make changes or understand the difference between a kilobit and a gigabit.

We'd all make the switch in a heartbeat, but the kind of people who join an online forum to obsesses over the technical details of spacecraft aren't a representative sample of the general population. It seems most people would rather not worry about it.
You haven't seen the level of hatred directed at our local provider, then.  Several of my neighbors are using 4G hotspots, even at a price penalty, to avoid the cable provider. 

Plus, when you have an existing market player able to leverage the force of government to protect its business (see Herb's example) you see "apathy". 


Title: Re: Starlink : General Discussion - Thread 2
Post by: DistantTemple on 06/15/2019 06:31 pm
Google cable required a physical route, preferably via existing poles, easements etc, or new trenches, poles and permissions. SX needs none of that.

EM appeals to a lot of markets with Starlink. 1) inaccessible/poor access to existing connections. 2) Higher speed.... assumed to be at a a fair price. 3) Low latency. He was just on E3 talking with Todd Howard, enjoying the company of gamers. The plug for Starlink only came in reply to a question about latency. I think he said <30ms from anywhere in the world! and in a later layer of satellites <10ms NOTE*. He stated it was one of the design criteria, to make it effective for gaming. (As well as talking about how many exceptional programmers started on games.) And I add, as VR enters gaming, and remote working, low latency and bandwidth will be needed.

No there are too many fires being cultivated, all pushing for Starlink-like performance. It will not be ignored.

As for multiple users on one antenna. For blocks of apartments its bound to happen. For offices, schools, hospitals etc, there will be a higher bandwidth connection. etc. So I expect Starlink will offer a suitable product, that can be highly multi user. (Edit: Maybe not alert Comcast that he can hijack their urban subscribers)
*(Seems bonkers to me as I get light taking 66ms to travel 20,000Km, half way round the earth!)
Title: Re: Starlink : General Discussion - Thread 2
Post by: Ludus on 06/15/2019 07:19 pm
I'd bet I could get plenty of people in my subdivision (~250 houses) to go in together on a Starlink terminal just to give a middle finger to our local provider...

History suggests otherwise. When Google Fiber rolled out tremendously better service at low prices, they found way less uptake than they needed to make it viable. People just sort of shrugged and continued with whatever didn't require them to make changes or understand the difference between a kilobit and a gigabit.

We'd all make the switch in a heartbeat, but the kind of people who join an online forum to obsesses over the technical details of spacecraft aren't a representative sample of the general population. It seems most people would rather not worry about it.
You haven't seen the level of hatred directed at our local provider, then.  Several of my neighbors are using 4G hotspots, even at a price penalty, to avoid the cable provider. 

Plus, when you have an existing market player able to leverage the force of government to protect its business (see Herb's example) you see "apathy".

This came out as a factor even in Elon’s original presentation of Starlink in Seattle where he was recruiting engineers and didn’t expect it to go public. There was cheering making a few words inaudible over the prospect of replacing the big telecom ISPs. The numbers have always meant urban markets would never be handled for large fractions of customers but Starlink could still be an alternative. The issues kind of balance out. Lot’s of people in cities don’t care enough to switch which is fine since the system can’t handle them anyway. There is capacity to give interested customers in cities an alternative. There are tens of millions of underserved people in rural areas as a base.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Kragrathea on 06/15/2019 10:56 pm
Can someone who knows chime in on how many base stations one sat can reasonably expect to talk to at one time? As I understand it a phased array antenna uses signal processing to pick out individual sources. And these sources are high frequency wide band.  There must be a limit to how many a modern signal processor can handle at one time.   
Title: Re: Starlink : General Discussion - Thread 2
Post by: oldAtlas_Eguy on 06/16/2019 03:43 am
The sat would likely not steer its spot over an area. It would likely use the same similar methodology of time share slots for uplink scheduled by the sat by sending the ground terminals their transmission package time slots. This is called Time division multiple access (TDMA). WiFi works in a similar manner.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Nomadd on 06/16/2019 04:06 am
The sat would likely not steer its spot over an area. It would likely use the same similar methodology of time share slots for uplink scheduled by the sat by sending the ground terminals their transmission package time slots. This is called Time division multiple access (TDMA). WiFi works in a similar manner.
I suspected they might do that, since high gain up and low gain down sort of leads that way.
 The problem with it is the routing. It would be good with early sats that just bounce the signal to a ground station, but in the future, when the sats route through each other and they're trying to minimize lag, the conversations are going to be going every which direction. The sat routers are going to make one armed paperhangers look lazy.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Barley on 06/16/2019 05:13 am
Modern WiFi (802.11ac) uses beam forming, a type of phased array.  I'd expect starlink to do the same for the same reasons.

Higher antenna gain gives greater rejection of noise and requires less transmission power.  It would also allow you to reuse frequencies in cells smaller than 1,000,000 km^2.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Kragrathea on 06/16/2019 05:46 am
Wifi doesn't work with 10,000s or 100,000s of simultaneous connections. Thats what a single sat would have to do if everyone who hates comcast puts a dish on the roof.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Robotbeat on 06/16/2019 06:30 am
Wifi doesn't work with 10,000s or 100,000s of simultaneous connections. Thats what a single sat would have to do if everyone who hates comcast puts a dish on the roof.
And?
Title: Re: Starlink : General Discussion - Thread 2
Post by: Kragrathea on 06/16/2019 07:50 am
Wifi doesn't work with 10,000s or 100,000s of simultaneous connections. Thats what a single sat would have to do if everyone who hates comcast puts a dish on the roof.
And?
And so it isn't relevant to the question: How many connections can a phased array sat be reasonably expected to handle at once.
Title: Re: Starlink : General Discussion - Thread 2
Post by: ZChris13 on 06/16/2019 07:55 am
Wifi doesn't work with 10,000s or 100,000s of simultaneous connections. Thats what a single sat would have to do if everyone who hates comcast puts a dish on the roof.
And?
And so it isn't relevant to the question: How many connections can a phased array sat be reasonably expected to handle at once.
the relevant stats are how many connections it can be expected to handle, the area that the satellite services, the maximum boxes per area density derived from this, and the general housing density of various zones of population to give that number context
Title: Re: Starlink : General Discussion - Thread 2
Post by: dondar on 06/16/2019 10:01 am
Can someone who knows chime in on how many base stations one sat can reasonably expect to talk to at one time? As I understand it a phased array antenna uses signal processing to pick out individual sources. And these sources are high frequency wide band.  There must be a limit to how many a modern signal processor can handle at one time.   
the process is called "beam forming" and is not different from the 5G designs. I see there are plenty of sufficiently good explanations of 5G on the interweb. Refer there.

Already Ku range bids excellent spacial separation of the sources and "theoretically" even complex modulations can be supported. Hence no need for WCDMA separation. But! Technical realization complexities are a bitch.
Math basis (MIMO communications) was done by the beginning of 2000 though.
there are no fundamental restrictions to support multiple users at the same time, more of it outside of cities (i.e. if direct links are available) the separation process is straightforward. ASICs thanks to the bitcoin craze grew up considerably so there are no restrictions there as well.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Jcc on 06/16/2019 04:21 pm
Wifi doesn't work with 10,000s or 100,000s of simultaneous connections. Thats what a single sat would have to do if everyone who hates comcast puts a dish on the roof.
And?
And so it isn't relevant to the question: How many connections can a phased array sat be reasonably expected to handle at once.
the relevant stats are how many connections it can be expected to handle, the area that the satellite services, the maximum boxes per area density derived from this, and the general housing density of various zones of population to give that number context

Another relevant stat is the average number of end users per ground station. Especially for apartment buildings and condos it makes a lot of sense to do connection sharing.
Title: Re: Starlink : General Discussion - Thread 2
Post by: DigitalMan on 06/17/2019 05:19 pm
I wonder, once the laser-equipped sats are launched, would it be possible to use one of the lasers to determine altitude?  Perhaps place retroreflectors on some of the ground stations?

It would be interesting I think if you are determined to have a large constellation with a minimum of babysitting. Another element would be using the routine communications between sats to track changes to their relative positions.

edit: I suppose you could measure altitude various ways from a ground station without retroreflectors.
Title: Re: Starlink : General Discussion - Thread 2
Post by: dglow on 06/17/2019 07:43 pm
So now the key market is people that could buy service from HNS and Viasat?

I thought the low-latency was the key to unlocking big money in HFT markets.
The HFT telecon market is small. There’s not “big money” there. This idea was never mentioned by Elon or SpaceX, it’s just an internet thing.

Realize that HFT markets have dedicated point to point microwave links that for the most part can get even lower latency.

Over land, yes. Across oceans it's still slow fiber. If SpaceX can get NYC–London under 50ms they'll have a hit.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Asteroza on 06/18/2019 12:41 am
So now the key market is people that could buy service from HNS and Viasat?

I thought the low-latency was the key to unlocking big money in HFT markets.
The HFT telecon market is small. There’s not “big money” there. This idea was never mentioned by Elon or SpaceX, it’s just an internet thing.

Realize that HFT markets have dedicated point to point microwave links that for the most part can get even lower latency.

Over land, yes. Across oceans it's still slow fiber. If SpaceX can get NYC–London under 50ms they'll have a hit.

Apparently the HFT guys are doing shortwave to cut out the fiber repeaters, or at least trying.

https://sniperinmahwah.wordpress.com/2018/05/07/shortwave-trading-part-i-the-west-chicago-tower-mystery/ (https://sniperinmahwah.wordpress.com/2018/05/07/shortwave-trading-part-i-the-west-chicago-tower-mystery/)

So the standard to beat is shortwave bounce latency (and the unreliability of the ionosphere).

and for added crazy

http://blogs.reuters.com/felix-salmon/2012/05/04/the-neutrino-arbitrage/ (http://blogs.reuters.com/felix-salmon/2012/05/04/the-neutrino-arbitrage/)

pointing neutrinos THROUGH the earth is probably a shorter distance than a orbital lasercomm relay...
Title: Re: Starlink : General Discussion - Thread 2
Post by: josephcouvillion on 06/18/2019 03:08 pm
Any clues as to Starlinks's downlink ground station costs?

It occurs to me that in addition to the low latency market, and the middle of no where market you have the extended suburbs, and other last mile problems market. Starlink doesn't need inter-satellite lasers to serve that market just a downlink station that hooks into existing backhauls in the city.

My area of town has lousy infrastructure the phone lines are crappy, often even for analog phone lines. Cable is also unreliable and prone to outages when it rains. but if I could use Starlink as a super WISP all that broken copper isn't a problem.
Title: Re: Starlink : General Discussion - Thread 2
Post by: rsdavis9 on 06/18/2019 03:17 pm
Any clues as to Starlinks's downlink ground station costs?

It occurs to me that in addition to the low latency market, and the middle of no where market you have the extended suburbs, and other last mile problems market. Starlink doesn't need inter-satellite lasers to serve that market just a downlink station that hooks into existing backhauls in the city.

My area of town has lousy infrastructure the phone lines are crappy, often even for analog phone lines. Cable is also unreliable and prone to outages when it rains. but if I could use Starlink as a super WISP all that broken copper isn't a problem.

Yup.
I have land 60 miles from boston. I have friends living near there and the cable company just stopped 1/4 mile short of their house. They are at least 2 miles to center of town for dsl. No cable. Cell phone coverage barely. Population 1300.

It will be interesting to see how starlink will allow people like this(60 miles) to hook up and prevent people in the near suburbs(10 miles) from hooking up and saturating the same satellites.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Mandella on 06/18/2019 03:26 pm
Any clues as to Starlinks's downlink ground station costs?

It occurs to me that in addition to the low latency market, and the middle of no where market you have the extended suburbs, and other last mile problems market. Starlink doesn't need inter-satellite lasers to serve that market just a downlink station that hooks into existing backhauls in the city.

My area of town has lousy infrastructure the phone lines are crappy, often even for analog phone lines. Cable is also unreliable and prone to outages when it rains. but if I could use Starlink as a super WISP all that broken copper isn't a problem.

I do fully expect there to be rain fade issues with Starlink, just as with existing satellite and cellular coverage. That said, I wouldn't mind being surprised. One mitigating factor might be often loss of signal with traditional satellite is due to one towering thundercloud passing between the ground dish and distant GSO transmitter -- the ability to switch between several different LEO satellites at all times might keep signal loss to a minimum during summer storm time.
Title: Re: Starlink : General Discussion - Thread 2
Post by: russianhalo117 on 06/19/2019 04:34 am
So now the key market is people that could buy service from HNS and Viasat?

I thought the low-latency was the key to unlocking big money in HFT markets.
The HFT telecon market is small. There’s not “big money” there. This idea was never mentioned by Elon or SpaceX, it’s just an internet thing.

Realize that HFT markets have dedicated point to point microwave links that for the most part can get even lower latency.

Over land, yes. Across oceans it's still slow fiber. If SpaceX can get NYC–London under 50ms they'll have a hit.

Apparently the HFT guys are doing shortwave to cut out the fiber repeaters, or at least trying.

https://sniperinmahwah.wordpress.com/2018/05/07/shortwave-trading-part-i-the-west-chicago-tower-mystery/ (https://sniperinmahwah.wordpress.com/2018/05/07/shortwave-trading-part-i-the-west-chicago-tower-mystery/)

So the standard to beat is shortwave bounce latency (and the unreliability of the ionosphere).

and for added crazy

http://blogs.reuters.com/felix-salmon/2012/05/04/the-neutrino-arbitrage/ (http://blogs.reuters.com/felix-salmon/2012/05/04/the-neutrino-arbitrage/)

pointing neutrinos THROUGH the earth is probably a shorter distance than a orbital lasercomm relay...
Shortwave band antenna networks use more power to operate than several other bands. That is one reason why terrestrial SW, MW and LW radio stations are shutting down in several countries.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Asteroza on 06/19/2019 07:00 am
So now the key market is people that could buy service from HNS and Viasat?

I thought the low-latency was the key to unlocking big money in HFT markets.
The HFT telecon market is small. There’s not “big money” there. This idea was never mentioned by Elon or SpaceX, it’s just an internet thing.

Realize that HFT markets have dedicated point to point microwave links that for the most part can get even lower latency.

Over land, yes. Across oceans it's still slow fiber. If SpaceX can get NYC–London under 50ms they'll have a hit.

Apparently the HFT guys are doing shortwave to cut out the fiber repeaters, or at least trying.

https://sniperinmahwah.wordpress.com/2018/05/07/shortwave-trading-part-i-the-west-chicago-tower-mystery/ (https://sniperinmahwah.wordpress.com/2018/05/07/shortwave-trading-part-i-the-west-chicago-tower-mystery/)

So the standard to beat is shortwave bounce latency (and the unreliability of the ionosphere).

and for added crazy

http://blogs.reuters.com/felix-salmon/2012/05/04/the-neutrino-arbitrage/ (http://blogs.reuters.com/felix-salmon/2012/05/04/the-neutrino-arbitrage/)

pointing neutrinos THROUGH the earth is probably a shorter distance than a orbital lasercomm relay...
Shortwave band antenna networks use more power to operate than several other bands. That is one reason why terrestrial SW, MW and LW radio stations are shutting down in several countries.

A frequently cited example is the death of the LORAN navigation beacon network (though there is the occasional noises of eLORAN making a comeback for navigation system diversity in the face of loss/jamming of GPS)

There are other factors as well leading to the shutdown of long range relay microwave such as the former AT&T Long Lines network, though the usual reason is servicing the very remote relay towers in rural areas, compared to fiber optic systems that typically follow existing highways/railways/powerlines and are thus easier to reach and repair. Most of the HFT microwave usage is line of sight to an exchange from a datacenter (though allegedly there were some private HFT lines reusing former Long Lines sites), while the shortwave stuff is generally intercontinental/international distances.

AT&T Long Lines Network (https://en.wikipedia.org/wiki/Microwave_transmission#Microwave_radio_relay)

Regaining the latency reduction of reduced relays via Starlink helps anything with realtime considerations, without the private upkeep costs of a Long Lines system, and for the shortwave operators, switching to Starlink avoids the variability of atmospheric conditions affecting your ionosphere bounce performance parameters.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 06/19/2019 03:27 pm
Neutrino thread (https://forum.nasaspaceflight.com/index.php?topic=48385.0)
Title: Re: Starlink : General Discussion - Thread 2
Post by: OTV Booster on 06/19/2019 10:28 pm
However mounting a pizza box size trainable antenna on the Tesla semi seem a lot more doable. Think most trucking companies wants internet connectivity with their trucks just for vehicle tracking alone.
And I would think that semis are also far more likely to be out of range of cell data coverage than passenger vehicles are.

Trucks, not so much. Personal experience.

Systems are genericly known as qualcomm’s for obvious reasons. First gen was sat only. Latency not an issue. Second gen cell w/sat fallback as an option. Latency not an issue. Loss of signal very rare these days. Latest systems do WiFi for the driver, cargo/reefer status log status and driver/collision cams. Latency only an issue for driver WiFi. Most companies could care less. Bandwidth maybe becoming an issue.

Ships could be a customer. Trains & busses if offering WiFi to passengers. Back in the 90’s I knew a guy on a microwave crew for th Santa Fe. They did a lot to keep operational info moving. Most track parallels major highways so cell should be available. Maybe a customer. Maybe not.

Phil
Title: Re: Starlink : General Discussion - Thread 2
Post by: Tulse on 06/20/2019 07:41 pm
Latency for semis might become an issue once autonomous driving becomes prevalent, as one would want a fairly fast connection in case remote manual control was necessary.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Asteroza on 06/20/2019 11:37 pm
Latency for semis might become an issue once autonomous driving becomes prevalent, as one would want a fairly fast connection in case remote manual control was necessary.

There are a few autonomous truck startups that are sorta doing that now, with highway driving autonomous, and a remote safety driver used for highway exits/entries.
Title: Re: Starlink : General Discussion - Thread 2
Post by: SWGlassPit on 06/21/2019 09:48 pm
TS Kelso (of CelesTrak) has some concerns about the tracking of the constellation:

https://twitter.com/TSKelso/status/1141906661499711491
Title: Re: Starlink : General Discussion - Thread 2
Post by: Warby12 on 06/22/2019 11:47 am
TS Kelso (of CelesTrak) has some concerns about the tracking of the constellation:

https://twitter.com/TSKelso/status/1141906661499711491

Hi SWGlassPit, Can you possibly explain this for me?
Title: Re: Starlink : General Discussion - Thread 2
Post by: Robotbeat on 06/22/2019 01:15 pm
TS Kelso (of CelesTrak) has some concerns about the tracking of the constellation:

https://twitter.com/TSKelso/status/1141906661499711491

Hi SWGlassPit, Can you possibly explain this for me?
TLEs haven’t been updated for a bit, which can be done by government agencies or possibly by amateur observations. The fact that neither of them have been updating the TLEs means the satellites are very dim.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 06/22/2019 01:51 pm
The fact that neither of them have been updating the TLEs means the satellites are very dim.

This is nonsense.  It says nothing about how bright the satellites are.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 06/22/2019 03:10 pm
Can you possibly explain this for me?

When a bunch of objects get released into similar orbits it can be difficult for the organization that tracks them to reliably keep track of which is which until they separate a little and get into stable orbits.  Aside from being a lot of objects, the SpaceX satellites have (almost) all been constantly changing their orbits as they climb to their operational altitude which makes things even trickier. 

That tracking database (the public interface for it is space-track.org) is used to warn satellite operators when something is going to come close to their sat so they can take a look and determine if any action is needed.  If the data isn't up to date then the analysis of possible collisions won't be correct.  Kelso is advocating for SpaceX to set up a system like Planet uses, where they publicly share their data on the orbits of their satellites.  We don't really know what kind of sharing is going on between SpaceX and 18 SPCS (USAF 18th Space Control Squadron), there should be some data sharing going on there but it's odd that the SpaceX orbital data isn't getting updated regularly if that sharing is happening.
Title: Re: Starlink : General Discussion - Thread 2
Post by: speedevil on 06/22/2019 09:21 pm
The fact that neither of them have been updating the TLEs means the satellites are very dim.

This is nonsense.  It says nothing about how bright the satellites are.
It at least has some correlation, I was going to attempt to do a video of the above train, and feed data to others as well as try getting TLEs myself, but they were not bright enough to see in my poor sky.
Title: Re: Starlink : General Discussion - Thread 2
Post by: drzerg on 06/22/2019 09:30 pm
if spacex have comms with sats and they could determine their positions themselves via star tracker i think spacex knows exact TLE every turn or even more often 
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 06/22/2019 09:37 pm
The fact that neither of them have been updating the TLEs means the satellites are very dim.

This is nonsense.  It says nothing about how bright the satellites are.
It at least has some correlation, I was going to attempt to do a video of the above train, and feed data to others as well as try getting TLEs myself, but they were not bright enough to see in my poor sky.

It doesn't.  18 SPCS isn't running outside with binoculars to try and find them.
Title: Re: Starlink : General Discussion - Thread 2
Post by: RedLineTrain on 06/22/2019 11:10 pm
Interesting aspect of how the competition between Starlink and Oneweb is playing out:  Oneweb has really staffed up in comparison to Starlink.  Oneweb already has 750+ employees between the DC suburbs, Toulouse, and Melbourne, Florida.  Starlink has about one-third that amount.

Is this a matter of spending efficiency or preparedness for scaling?
Title: Re: Starlink : General Discussion - Thread 2
Post by: Draggendrop on 06/22/2019 11:20 pm
Interesting aspect of how the competition between Starlink and Oneweb is playing out:  Oneweb has really staffed up in comparison to Starlink.  Oneweb already has 750+ employees between the DC suburbs, Toulouse, and Melbourne, Florida.  Starlink has about one-third that amount.

Is this a matter of spending efficiency or preparedness for scaling?

This appears to be a wide open statement.

Could you place a little more perspective as to how you find this interesting. You have not given numbers for various employment functions to do a comparison as well as the labour intensity required for the various functions. The employee numbers stated are meaningless without context ( they could all be lobbyists for all I know).
Title: Re: Starlink : General Discussion - Thread 2
Post by: Draggendrop on 06/22/2019 11:57 pm
TS Kelso (of CelesTrak) has some concerns about the tracking of the constellation:

https://twitter.com/TSKelso/status/1141906661499711491

Hi SWGlassPit, Can you possibly explain this for me?

I would not put too much into this tweet.

18 SPCS is tasked with monitoring and avoidance, among many other duties.

This briefing, pdf will give insight...
https://advancedssa.com/assets/img/workshop/presentations/JSpOC-18SPCS_CONOPS.pdf (https://advancedssa.com/assets/img/workshop/presentations/JSpOC-18SPCS_CONOPS.pdf)

18 SPCS has many resources available  to them and are in possession of more detailed data than just TLE's.

If there is an issue, they are able to communicate directly with the payload owner..
https://www.af.mil/News/Article-Display/Article/1335482/18th-space-control-squadron-keeping-watch-up-above/ (https://www.af.mil/News/Article-Display/Article/1335482/18th-space-control-squadron-keeping-watch-up-above/)

The 18th Space Control Squadron maintains the space catalog.
https://www.afspc.af.mil/News/Article-Display/Article/1459151/18th-spcs-stands-guard-over-space/ (https://www.afspc.af.mil/News/Article-Display/Article/1459151/18th-spcs-stands-guard-over-space/)

The latest info is not neccessarily in the catalog.

I am sure 18 SPCS and SpaceX are more than aware of the entire situation.

The men and women of 18SPCS do an outstanding job, a thankless job at times. One must be careful to not "cry wolf" too often...

just my 2 cents.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 06/23/2019 12:11 am
This is a visualization from Celestrak at
https://celestrak.com/cesium/orbit-viz.php?tle=/satcat/tle.php?INTDES=2019-029&satcat=/pub/satcat.txt&orbits=64&pixelSize=3&samplesPerPeriod=9

If you do look for the Starlink satellites and see some go by, would you know which of the 64 objects they are without already having accurate TLEs for them?  If you have fairly frequent observations you can probably make a good guess, and 18 SPCS should have fairly frequent observations, but if it takes manual analysis to sort everything out every day I wonder if 18 SPCS is really set up for dealing with that.  It's an unusual number of objects for them to have to deal with during orbit raising.  SpaceX has that information.  If they're sharing it with 18 SPCS, it might still take manual processing on the USAF side, which they might not be used to doing with great frequency.  These large launches might be a learning process for both sides.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Draggendrop on 06/23/2019 12:42 am
Quite true.

At the same time, this is a visualization of TLE data using a specific platform (and there are a few), which is a nice GUI.

Some payloads also have GPS and we have many ground assets to determine positional (ephemeris)data as well.

All I am stating is that TLE's in the catalog at any moment are not the whole story, just a nice data set portrayed in compact fashion and this information can be refined much further, as is done by 18SPCS, when they have the time and updated in the catalog but, it may not be the latest due to internal priorities. This could even be a staffing problem due to budget.

In my opinion, the real issue is one of a regulatory nature. We can't expect to put an expensive tracking system on a student cubesat, but we could at least require something better on commercial payloads. At present, launch providers and payloads are conforming to the regulations in place.

It is going to be difficult to identify a close set of payloads unless methods are in place for future launches and it must be affordable.

I have not heard 18SPCS's side of the story on this matter but believe that they have this in hand as best as they can, for now.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Robotbeat on 06/23/2019 01:59 am
The fact that neither of them have been updating the TLEs means the satellites are very dim.

This is nonsense.  It says nothing about how bright the satellites are.
It at least has some correlation, I was going to attempt to do a video of the above train, and feed data to others as well as try getting TLEs myself, but they were not bright enough to see in my poor sky.

It doesn't.  18 SPCS isn't running outside with binoculars to try and find them.
My mistake. I know that they DO rely on amateur observations for classified satellites.
Title: Re: Starlink : General Discussion - Thread 2
Post by: dondar on 06/23/2019 08:20 am
quoted StarLink sats are  all parked (see 540km circular orbit) and according to SpaceX are all active. Why 18SPCS should divert their precious resources to track normal objects on a boring for them orbit?
Key reference here are the rest of the not-observed objects. They are all boring.

One would be interested  (especially astronomical societies) to have precise mapping of all sats in order to code observation patterns and it is indeed would be a nice subj for the next step of the Space regulations, but gosh this SpaceX bashing is really ridiculous.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 06/23/2019 01:20 pm
quoted StarLink sats are  all parked (see 540km circular orbit) and according to SpaceX are all active. Why 18SPCS should divert their precious resources to track normal objects on a boring for them orbit?
Key reference here are the rest of the not-observed objects. They are all boring.

One would be interested  (especially astronomical societies) to have precise mapping of all sats in order to code observation patterns and it is indeed would be a nice subj for the next step of the Space regulations, but gosh this SpaceX bashing is really ridiculous.

A little more than half of the sats are very close to the 550km circular orbit.  Some are a little above, some are still orbit raising, three still haven't moved much from the deployment orbit, and one appears to be deorbiting.  18SPCS doesn't just start ignoring objects because SpaceX fans want them to.  There are no "boring" objects in orbit, they all need to be tracked.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Robotbeat on 06/23/2019 03:25 pm
quoted StarLink sats are  all parked (see 540km circular orbit) and according to SpaceX are all active. Why 18SPCS should divert their precious resources to track normal objects on a boring for them orbit?
Key reference here are the rest of the not-observed objects. They are all boring.

One would be interested  (especially astronomical societies) to have precise mapping of all sats in order to code observation patterns and it is indeed would be a nice subj for the next step of the Space regulations, but gosh this SpaceX bashing is really ridiculous.

A little more than half of the sats are very close to the 550km circular orbit.  Some are a little above, some are still orbit raising, three still haven't moved much from the deployment orbit, and one appears to be deorbiting.  18SPCS doesn't just start ignoring objects because SpaceX fans want them to.  There are no "boring" objects in orbit, they all need to be tracked.
NORAD has to track all of this already, don’t they? They have radar.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 06/23/2019 07:17 pm
NORAD has to track all of this already, don’t they? They have radar.

21st Space Wing
Quote
The 21st Space Wing is headquartered at Peterson Air Force Base, Colo., and is the Air Force's only organization providing missile warning and space control to unified combatant commanders worldwide.

Home of 53 mission partners supported on Peterson AFB and Cheyenne Mountain Air Force Station, including North American Aerospace Defense Command (NORAD), U.S. Northern Command, Air Force Space Command (AFSPC), Space and Missile Defense Command/Army Strategic Command and the 302nd Airlift Wing (USAF Reserves).

18th Space Control Squadron
Quote
LOCATION
The 18th Space Control Squadron (SPCS) at Vandenberg Air Force Base, CA, is located 160 miles northwest of Los Angeles, CA. The squadron is a geographically separated unit of the 21st Space Wing, Peterson Air Force Base, CO.
...
MISSION
- Deliver foundational Space Situational Awareness to assure global freedom of action in space

The squadron is the newest addition to the 21st Space Wing. It is tasked with providing 24/7 support to the space sensor network (SSN), maintaining the space catalog and managing United States Strategic Command’s (USSTRATCOM) space situational awareness (SSA) sharing program to United States, foreign government, and commercial entities. The squadron also conducts advanced analysis, sensor optimization, conjunction assessment, human spaceflight support, reentry/break-up assessment, and launch analysis. In addition, 18 SPCS also oversees 18 SPCS Detachment 1, located in Dahlgren, VA.

EQUIPMENT AND FACILITIES
The squadron is jointly located with the Joint Space Operations Center in Building 8401 at Vandenberg AFB, CA. The squadron operates Space Defense Operations Center (SPADOC) and the Astrodynamic Support Workstation (ASW) to task and receive observation data from the SSN and provide that data to DoD and non-DoD customers.

Approximately 64 military and 25 civil service people are permanently assigned to 18 SPCS. Around thirty military personnel are assigned to the operations flight, which is responsible for SPADOC and ASW operations. The remainder of the assigned military and civilian workers provide support and advanced functions in support of 18 SPCS operations.

HISTORY
...On July 22, 2016, 18 SPCS was reactivated at Vandenberg AFB, CA to perform the SSA sensor tasking mission.

edit: This recent article mentions the current state of affairs with the computer systems:
https://breakingdefense.com/2019/04/what-about-jms-air-force-reanimates-old-clunker-space-tracking-system/
Title: Re: Starlink : General Discussion - Thread 2
Post by: Draggendrop on 06/23/2019 08:14 pm
Just to help out....

Going beyond 18 SPCS, we have international involvement. Here is a very simplified brief...

https://swfound.org/media/205874/swf_ssa_fact_sheet.pdf (https://swfound.org/media/205874/swf_ssa_fact_sheet.pdf)

This does not include Space Fence which was due 4th Qtr of 2019 (may have shifted) as well as access to other agency assets such as missile defence.

https://en.wikipedia.org/wiki/Space_Fence (https://en.wikipedia.org/wiki/Space_Fence)

There are many billions of dollars  worth of equipment in operation and available in the near future. 18 SPCS has multiple resources and will have enhanced real time mass tracking for use with present multiple collision filtering abilities.

I have not seen any requirements for TLE's to be updated in real time. The data that 18 SPCS has available will always be more accurate. They will communicate "issues" with the owner/operators directly. Unless someone would prefer a website that processes TLE data, that they were given. When one has 6 and 7 figure satellite/constellation assets...my money would be on the source.

Sorry about being blunt...this is why I lean towards SpaceX and 18 SPCS having a good handle on the situation.
 
Title: Re: Starlink : General Discussion - Thread 2
Post by: dondar on 06/25/2019 08:45 am
quoted StarLink sats are  all parked (see 540km circular orbit) and according to SpaceX are all active. Why 18SPCS should divert their precious resources to track normal objects on a boring for them orbit?
Key reference here are the rest of the not-observed objects. They are all boring.

One would be interested  (especially astronomical societies) to have precise mapping of all sats in order to code observation patterns and it is indeed would be a nice subj for the next step of the Space regulations, but gosh this SpaceX bashing is really ridiculous.

A little more than half of the sats are very close to the 550km circular orbit.  Some are a little above, some are still orbit raising, three still haven't moved much from the deployment orbit, and one appears to be deorbiting.  18SPCS doesn't just start ignoring objects because SpaceX fans want them to.  There are no "boring" objects in orbit, they all need to be tracked.
18SPCS is not busy with tracking and reporting of all space objects. It's the mission for NORAD related unites' and their capabilities (and reports) are not public obviously.
18SPCS is busy with the safety of space operations and they focus primarily on the objects which change orbits or operate on unusual (read highly eccentric) orbits. Their job is to provide reliable data in simple numeric format which can be used by interested parties to feed their guiding models and to avoid possible collisions.

Anyway let take the tweet seriously for a moment. According to it at least a couple of Starlink pizzas have reached stable orbit by 6 of June. I call it BS. (it should be ~12-14 of june). And all corresponding TLE dating I call questionable. More of it if you are not lazy you can easily find confirmation of that suspicion.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 06/25/2019 12:16 pm
18SPCS is not busy with tracking and reporting of all space objects. It's the mission for NORAD related unites' and their capabilities (and reports) are not public obviously.

That is false.  18SPCS tracks and catalogs all objects (although they don't publicly share data on many military satellites).  NORAD did that a long time ago.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Lar on 06/25/2019 04:18 pm
is this subtopic interesting enough to merit a carve-out?
Title: Re: Starlink : General Discussion - Thread 2
Post by: Asteroza on 06/25/2019 11:34 pm
is this subtopic interesting enough to merit a carve-out?

Traffic monitoring and control is going to be an increasing concern in the age of megaconstellations, to prevent Kessler syndrome if nothing else. Perhaps a new orbit ops subforum perhaps, to merge all the megaconstellation threads with the spacecraft ops/astrogation threads?
Title: Re: Starlink : General Discussion - Thread 2
Post by: su27k on 06/27/2019 05:04 pm
TS Kelso (of CelesTrak) has some concerns about the tracking of the constellation:

https://twitter.com/TSKelso/status/1141906661499711491

Current status, situation is much improved now, only 4 Starlink satellites have TLE older than 5 days.
Title: Re: Starlink : General Discussion - Thread 2
Post by: dglow on 06/27/2019 06:08 pm
Good to know that somebody is on it.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 06/27/2019 07:48 pm
Your tired meme doesn't really apply in this case.  The process is not all internal to SpaceX.
Title: Re: Starlink : General Discussion - Thread 2
Post by: dglow on 06/27/2019 10:56 pm
Your tired meme doesn't really apply in this case.  The process is not all internal to SpaceX.

Ouch. Perhaps 'my' meme is more about injecting a touch of fun than finding a perfect analogy. YMMV, of course.
Title: Re: Starlink : General Discussion - Thread 2
Post by: NewSpaceIsFun on 06/28/2019 12:21 am
Your tired meme doesn't really apply in this case.  The process is not all internal to SpaceX.

Ouch. Perhaps 'my' meme is more about injecting a touch of fun than finding a perfect analogy. YMMV, of course.
I'd forgotten about that one, thanks for reposting. I found it funny and totally fits so many threads I read on here. Works even if you scratch out SpaceX and put some other entity in there.
Title: Re: Starlink : General Discussion - Thread 2
Post by: dondar on 06/28/2019 07:36 am
18SPCS is not busy with tracking and reporting of all space objects. It's the mission for NORAD related unites' and their capabilities (and reports) are not public obviously.

That is false.  18SPCS tracks and catalogs all objects (although they don't publicly share data on many military satellites).  NORAD did that a long time ago.
21st Operations Group does the tracking. 18SPCS does cataloging.
Direct quote:
Quote
The squadron is the newest addition to the 21st Space Wing. It is tasked with providing 24/7 support to the space sensor network (SSN), maintaining the space catalog and managing United States Strategic Command’s (USSTRATCOM) space situational awareness (SSA) sharing program to United States, foreign government, and commercial entities. The squadron also conducts advanced analysis, sensor optimization, conjunction assessment, human spaceflight support, reentry/break-up assessment, and launch analysis. In addition, 18 SPCS also oversees 18 SPCS Detachment 1, located in Dahlgren, VA.
They were formed as a cushion between uber secretive 21st and the commercial operators which cooperation is critical for the correct identification of space crap by 21st.

To return to the TLE. 18SPCS issue regularly updates. The data sets are good as long they are not changed.
If Starlink latest TLE is tagged by 20 days (erroneously as it's easy to check) it is still as good as 1 day old.
They request operators to submit in time forms with orbit changes etc. and on their side they provide collision avoidance services etc.
their site is https://www.space-track.org.

P.S. Indeed it would be nice if the NSF guys would make an article about what 18SPCS do and why their job is critically important (they provide and cure orbital data for the satellite operators).
But there is no such article so far, and the satellite data were used to attack SpaceX. Amazingly by the owner of CelesTrak who is supposed to "know better".
As long it is primarily SpaceX related the discussion place is here I believe.
Title: Re: Starlink : General Discussion - Thread 2
Post by: su27k on 06/29/2019 02:30 am
Sounds like there's some fighting over whether Starlink has “first to operate” status: https://www.geekwire.com/2019/spacex-reports-milestone-starlink-satellite-links-sparks-debate/

Quote
SpaceX said “Starlink is now the first NGSO [non-geosynchronous satellite orbit] system to operate in the Ku-band and communicate with U.S. ground stations, demonstrating the system’s potential to provide fast, reliable internet to populations around the world.”

That statement isn’t intended merely as a marketing boast: In documents filed earlier this month with the Federal Communications Commission, SpaceX says its “first to operate” status with the FCC means it can “select its frequencies first” if there’s a conflict with other satellite telecommunication networks in low Earth orbit.

SpaceX’s claim on that score has set off a flurry of regulatory filings from its rivals in the market for satellite broadband services, including the international OneWeb consortium and Canada’s biggest satellite operator, Telesat.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Robotbeat on 06/29/2019 02:43 am
OneWeb was always in the "I'm gonna take my spectrum and go home!" camp. No shed tears for them. But Telesat deserves to be given a fair shot.


...these being only moral statements, not legal ones. :)
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 06/29/2019 02:49 am
Personally I find SpaceX's argument kinda lacking, but we'll see what happens when the lawyers duke it out.  I'm not sure how much difference it will really make anyway, you still have to split the spectrum between the two constellations in those cases.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Robotbeat on 06/29/2019 12:56 pm
Personally I find SpaceX's argument kinda lacking, but we'll see what happens when the lawyers duke it out.  I'm not sure how much difference it will really make anyway, you still have to split the spectrum between the two constellations in those cases.
I think part of it is trying to strengthen their bargaining position. OneWeb always claimed to control more spectrum rights and for a while seemed to be ahead in deployment, which would give them a better position to argue for maintaining those rights (while preventing others like SpaceX from operating competitively), but SpaceX has now pulled ahead in deployment and appear to be ready for initial operations just as fast or faster than OneWeb.

OneWeb also seemed to want to establish “altitude rights” ostensibly for orbital debris safety, but also having the further benefit of gaining a monopoly near that altitude, another kind of valuable first-come-, first-serve property right that could in principle be worth a lot of money (like GPS slots).

Anyway, I think a lot of this is about bargaining position. The FCC wants to award spectrum to folks who will actually use it, not squatters, and SpaceX is appealing to that.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 06/29/2019 01:44 pm
I'm sure the FCC wants to make spectrum available to a US company too, and SpaceX is the only one in the game.  I've wondered if that is part of some of the quick approvals SpaceX has gotten.

This "first to operate" thing doesn't seem to be about the amount of spectrum they get in the sharing situations, but who gets to pick which part of the available spectrum they'll use.  I suppose that could allow you to make quicker connections if you're not having to check a couple frequencies to see which is in use?  The splitting shouldn't be random, I'd hope they arrange in advance which frequencies each system will use in those situations.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Draggendrop on 06/29/2019 03:29 pm
Just my opinion, but frequency allocation within the Ku band will be very important down the road with respect to interference. This has been covered in depth within the FCC filings and interference will not be tolerated. If one gets to choose prime regions of the spectrum, there will be less chance of being asked to modify or curtail use later on when issues with adjacent operators occur.
Title: Re: Starlink : General Discussion - Thread 2
Post by: billh on 07/02/2019 06:20 pm
Quote
"The failure of at least five percent of the first batch of SpaceX Starlink satellites has put a spotlight on the growing concerns that satellite megaconstellations could litter low Earth orbit with hundreds of dead satellites."

https://spacenews.com/starlink-failures-highlight-space-sustainability-concerns/
Title: Re: Starlink : General Discussion - Thread 2
Post by: Asteroza on 07/03/2019 12:25 am
Has the nature of the 3 "bad" sats been expanded upon? SpaceX claims initial contact, but it isn't clear if that meant afterwards power loss caused them to go silent (solar or battery failure), electric thruster failure preventing active deorbit but otherwise they are operating (they mention passive disposal), or partial solar failure preventing accumulation of enough power to operate the electric thruster?

The partial power case might show up as odd slight orbit changes downward every once in a while as the thrusters can't be operated on a full duty cycle.

Has anyone recently imaged the 3 sats? If they are still optically flaring that would suggest at least the solar panel deployed.
Title: Re: Starlink : General Discussion - Thread 2
Post by: docmordrid on 07/03/2019 12:52 am
From the StarLink media call tweeted by a CNBC correspondent

https://twitter.com/thesheetztweetz/status/1128787853310402561

Quote
@joroulette:
What are 3 biggest worries about functionality? Is #ProjectKuiper added competition?
|
Musk: "We feel pretty good about these satellites ... we are trying two different deployment mechanisms for the solar arrays."

Perhaps the 3 failed satellites were using an alternate array deployment mechanism which failed. After the batteries discharged, bye-bye.
Title: Re: Starlink : General Discussion - Thread 2
Post by: cuddihy on 07/03/2019 07:02 am
-first I've seen rounding out the discussion of 2 different types of deployment mechanisms for solar arrays

-interesting point by Matt Desch on how the reliability exceeding 2-3 times expected lifetime perversely creates a "sudden failure" on orbit, maybe years after expected lifetime, that results in a satellite being unable to deorbit or safed when it finally fails. This is an interesting point. So in this case, while commercially huge for the satellites to last longer than expected, it may be contributing to a space debris problem.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Chris Bergin on 07/03/2019 02:28 pm
Thread trimmed. If you want to discuss the quality level of another site, go on that site's comment section. The thread is about Starlink.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Rondaz on 07/05/2019 03:12 pm
Space Development Agency releases its first solicitation

by Sandra Erwin — July 4, 2019

The SDA is looking to develop an "agile, responsive next-generation space architecture."

https://spacenews.com/space-development-agency-releases-its-first-solicitation/
Title: Re: Starlink : General Discussion - Thread 2
Post by: Comga on 07/05/2019 04:22 pm
Space Development Agency releases its first solicitation

by Sandra Erwin — July 4, 2019

The SDA is looking to develop an "agile, responsive next-generation space architecture."

https://spacenews.com/space-development-agency-releases-its-first-solicitation/ (https://spacenews.com/space-development-agency-releases-its-first-solicitation/)

Starlink for SDA
Ha!
Who hear can envision a technical bromance between the architect of Constellation and the architect of Starship?
What more unlikely duo than Griffin and Musk?
Title: Re: Starlink : General Discussion - Thread 2
Post by: Zed_Noir on 07/05/2019 07:12 pm
<snip>
Starlink for SDA
Ha!
Who hear can envision a technical bromance between the architect of Constellation and the architect of Starship?
What more unlikely duo than Griffin and Musk?

Not bromance. It is more like the enemy of of my enemy is my friend.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 07/08/2019 02:59 am
Quote
PUBLIC SUMMARY

License to Operate a Private Remote Sensing Space System

On April 8, 2019, the Commercial Remote Sensing Regulatory Affairs Office of the National
Oceanic and Atmospheric Administration (NOAA CRSRA), an agency of the Department of
Commerce, granted a license to Space Exploration Technologies Corp. (SpaceX), to operate
Starlink, which is now owned by SpaceX Services, Inc., a SpaceX wholly-owned subsidiary.

The license authorizes the use of sixty electro-optical satellites in an orbital plane of 400-550km
circular at an approximate inclination of 53°. Each satellite in the system is allowed to carry a
single low-resolution panchromatic video imager. The imager will capture low-resolution images
and video of Earth and the satellite itself.

Name, mailing address and telephone number of the licensee:
SpaceX Services, Inc.
Space Exploration Technologies Corp.
1 Rocket Road
Hawthorne, CA 90250
Title: Re: Starlink : General Discussion - Thread 2
Post by: docmordrid on 07/08/2019 03:37 am
Quote
Quote
PUBLIC SUMMARY

License to Operate a Private Remote Sensing Space System


>
granted a license to Space Exploration Technologies Corp. (SpaceX), to operate Starlink, which is now owned by SpaceX Services, Inc., a SpaceX wholly-owned subsidiary.

The license authorizes the use of sixty electro-optical satellites in an orbital plane of 400-550km circular at an approximate inclination of 53°. Each satellite in the system is allowed to carry a single low-resolution panchromatic video imager. The imager will capture low-resolution images and video of Earth and the satellite itself.

Name, mailing address and telephone number of the licensee:

SpaceX Services, Inc.
Space Exploration Technologies Corp.
1 Rocket Road
Hawthorne, CA 90250

Assuming this is for the next flock,

Electro-optical = lasers?
Observing what, or...who?
DoD or SDA demo?
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 07/08/2019 03:41 am
Quote
Quote
PUBLIC SUMMARY

License to Operate a Private Remote Sensing Space System


>
granted a license to Space Exploration Technologies Corp. (SpaceX), to operate Starlink, which is now owned by SpaceX Services, Inc., a SpaceX wholly-owned subsidiary.

The license authorizes the use of sixty electro-optical satellites in an orbital plane of 400-550km circular at an approximate inclination of 53°. Each satellite in the system is allowed to carry a single low-resolution panchromatic video imager. The imager will capture low-resolution images and video of Earth and the satellite itself.

Name, mailing address and telephone number of the licensee:

SpaceX Services, Inc.
Space Exploration Technologies Corp.
1 Rocket Road
Hawthorne, CA 90250

Assuming this is for the next flock,

Electro-optical = lasers?
Observing what, or...who? DoD demo?

I'm assuming it was for the last launch since it was approved before then.  Electro optical is a digital camera.  I think it's mostly for observing the satellite itself, with Earth possibly in the background.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Mandella on 07/08/2019 05:33 am
IIRC, isn't the above just fallout from two years ago when NOAA suddenly noticed that the Go-Pros that SpaceX was using to observe its own rockets could also see the ground under them, so therefore a special license was needed.

I think it was specifically the cameras set to show off Starman in his Tesla, and they even had to cut off views from the second stage of the next launch while they worked out licensing details.

Edit to add: what I am getting at is that I imagine they just go ahead and get the license on any camera that can possibly see the Earth, even if that's not its primary function.

Or what gongora said....
Title: Re: Starlink : General Discussion - Thread 2
Post by: TRex on 07/08/2019 07:23 am
Electro Optic Systems Canberra Australia make lasers for detecting space junk
Title: Re: Starlink : General Discussion - Thread 2
Post by: Norm38 on 07/08/2019 04:09 pm
Where did the V0.9 / V1.0 verbage come from that's on the Manifest page?  Is that NSF internal, or something Musk said?  Just curious.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 07/08/2019 09:24 pm
The first launch was not the full production design, they lack the Ka-band payload.  They've been referred to as Starlink 0.9.  The next launch is supposed to be the production design (except for laser interconnects that will be added at some point in the future) with both Ku and Ka payloads, which would be version 1.0.
Title: Re: Starlink : General Discussion - Thread 2
Post by: ThomasGadd on 07/08/2019 11:34 pm
The first launch was not the full production design, they lack the Ka-band payload.  They've been referred to as Starlink 0.9.  The next launch is supposed to be the production design (except for laser interconnects that will be added at some point in the future) with both Ku and Ka payloads, which would be version 1.0.

This is a guess right?  We don't have evidence one way or the other when the inter-satellite links are added. 

For production, the cost and time time to setup all the ground stations that won't be need once the interlinks are in place.
Title: Re: Starlink : General Discussion - Thread 2
Post by: 2megs on 07/09/2019 01:54 am
For production, the cost and time time to setup all the ground stations that won't be need once the interlinks are in place.

I expect that they'll still want a ground station visible from every satellite after they have interlinks. Either way the total bandwidth into the constellation is going to equal total bandwidth out of the constellation [1]; it's just a question of how much of the backbone is in space versus on the ground.

[1] Caching the Netflix library in space or multicasting the top Twitch streamers is presumably a feature for Starlink v3.0.
Title: Re: Starlink : General Discussion - Thread 2
Post by: su27k on 07/09/2019 02:05 am
Three rules for building a megaconstellation (https://spacenews.com/three-rules-for-building-a-megaconstellation/)

Quote
RULE NO. 1: BUILD NEW TECH FAST
....
David Goldman, SpaceX’s director of satellite policy, said the company is taking lessons learned building rockets and applying those to its Starlink constellation.

“Rapid iteration is the DNA of the company… a lot of that has to do with [the fact] that we design and manufacture most of the components ourselves,” he said. It’s very integrated. If the technicians who are putting things together find something that can be improved, they can go straight to the engineer who designed it and that can be fixed on the fly. That’s how you can iterate as quickly as we can do today.”

Quote
RULE NO. 2: AUTOMATE SELECTIVELY
...
SpaceX is uploading tracking data for satellites and space debris from the U.S. Air Force’s Combined Space Operations Center and other sources, Goldman said, so Starlink satellites can autonomously fly around hazards — not unlike the self-driving electric cars Musk is building at Tesla.

Quote
RULE NO. 3: LEAVE ROOM FOR FAILURE
...
Goldman said SpaceX sought with its first big Starlink launch to establish that failures with something so new shouldn’t come as a surprise.

“We are not going to have another launch until we watch these for a little while to see what works and what doesn’t, and then we can build that into the next models to make sure that they are better,” he said. “I think the best thing you can do is just be honest with the public and tell everybody what you are up to, and don’t say you are going to have 100 percent reliability if you can’t accomplish that.”
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 07/09/2019 03:32 am
The first launch was not the full production design, they lack the Ka-band payload.  They've been referred to as Starlink 0.9.  The next launch is supposed to be the production design (except for laser interconnects that will be added at some point in the future) with both Ku and Ka payloads, which would be version 1.0.

This is a guess right?  We don't have evidence one way or the other when the inter-satellite links are added. 

For production, the cost and time time to setup all the ground stations that won't be need once the interlinks are in place.

Not a guess, this is what SpaceX (Elon) has said is going to happen.  The intersatellite links are not expected soon.  There could always be a change of plans, but I'd be surprised if they launch any with the intersatellite links before at least mid-2020, probably later than that.
Title: Re: Starlink : General Discussion - Thread 2
Post by: ThomasGadd on 07/09/2019 03:58 am
The first launch was not the full production design, they lack the Ka-band payload.  They've been referred to as Starlink 0.9.  The next launch is supposed to be the production design (except for laser interconnects that will be added at some point in the future) with both Ku and Ka payloads, which would be version 1.0.

This is a guess right?  We don't have evidence one way or the other when the inter-satellite links are added. 

For production, the cost and time time to setup all the ground stations that won't be need once the interlinks are in place.

Not a guess, this is what SpaceX (Elon) has said is going to happen.  The intersatellite links are not expected soon.  There could always be a change of plans, but I'd be surprised if they launch any with the intersatellite links before at least mid-2020, probably later than that.

Right.  I was trying to quantify soon.  Thanks.
Title: Re: Starlink : General Discussion - Thread 2
Post by: meekGee on 07/09/2019 09:07 pm
For production, the cost and time time to setup all the ground stations that won't be need once the interlinks are in place.

I expect that they'll still want a ground station visible from every satellite after they have interlinks. Either way the total bandwidth into the constellation is going to equal total bandwidth out of the constellation [1]; it's just a question of how much of the backbone is in space versus on the ground.

[1] Caching the Netflix library in space or multicasting the top Twitch streamers is presumably a feature for Starlink v3.0.
You can cache content in higher orbits, no?  All the way to GEO even..  or at least sun synchronous, so the same locale-specific cache is over the same TV markets region at 8 pm...
Title: Re: Starlink : General Discussion - Thread 2
Post by: Lar on 07/09/2019 09:29 pm
the V 1.0 ( versus V 0.9)  labeling is also via Musk, IIRC.
Title: Re: Starlink : General Discussion - Thread 2
Post by: freddo411 on 07/09/2019 10:26 pm
For production, the cost and time time to setup all the ground stations that won't be need once the interlinks are in place.

I expect that they'll still want a ground station visible from every satellite after they have interlinks. Either way the total bandwidth into the constellation is going to equal total bandwidth out of the constellation [1]; it's just a question of how much of the backbone is in space versus on the ground.

[1] Caching the Netflix library in space or multicasting the top Twitch streamers is presumably a feature for Starlink v3.0.

It's virtually impossible to have a ground station over every sat;   The oceans are vast.   I do expect there will be many ground stations, for performance, capacity, and political reasons.

It's possible to cache near the ends of the network, but I doubt this will be a feature of the early versions of Starlink.   

Title: Re: Starlink : General Discussion - Thread 2
Post by: Tomness on 07/11/2019 03:42 pm
Reading an article on my news feed about SpaceX needing a longer fairing for the disputed dod contract, how many more starlink pizza boxes could be on one flight with a 50% longer fairing?

Ie, would starlink pay for the longer fairing by reducing the number of launches by 10 out of hundreds?, 100 out of thousands???

Also, does enough S2 fuel remain to do a plane change? The certainly was no need to change planes for the first launch.

Bunch of tradeoffs on how much fuel S1 expends/where it lands, how much fuel S2 has to maneuver, how many pancakes in the stack.

The Starlink-1 mission was already a very hot reentry. They might be able to trade some upper stage margin to recover the booster, but the current design seems to nearly max out F9's payload mass capability to that orbit so a larger fairing probably wouldn't help much on F9.

Elon said they could have gotten few more on the current fairing but at the sacrifice of the first stage. So if they are forced to build a new fairing they could launch them on a recoverable FH. But they are looking at launching Starlink on Starship ASAP. So who knows if they they want to go that route yet. It might keep FH busy for a min.  But I imagine they are going to be up saleing FH soon.

Moved from specific mission thread
Title: Re: Starlink : General Discussion - Thread 2
Post by: AC in NC on 07/11/2019 05:41 pm
Launch costs are cheap.  10 isn't theoretically possible.  It's totally possible.  ISTM.
This assumes that radical plane changes from the satellites themselves is not possible.

Fair enough.  You know I always defer to your expertise with back-of-the-napkin (or better) figures.  :)   

I suppose (and I should probably refrain from this) I wish to rebut the original concern (quote: "I don’t see how SpaceX can insert the required 10 or so satellites").  My point is that replacing 10 sats is a non-issue.  As such my point doesn't assume radical plane changes are not possible.  It just holds that as an independent optimization exercise.

The question of whether or not SpaceX might launch 60 (or in a stretched fairing 90) sats (v0.9 or uprated in some way) to fill gaps and be capable of the plane changes needed to effectively distribute those where they are needed is an interesting question.  But I hold that the launch costs don't require it necessarily be solved.

Moved from Mission Specific thread
Title: Re: Starlink : General Discussion - Thread 2
Post by: Robotbeat on 07/12/2019 02:20 pm
Space Development Agency releases its first solicitation

by Sandra Erwin — July 4, 2019

The SDA is looking to develop an "agile, responsive next-generation space architecture."

https://spacenews.com/space-development-agency-releases-its-first-solicitation/ (https://spacenews.com/space-development-agency-releases-its-first-solicitation/)

Starlink for SDA
Ha!
Who hear can envision a technical bromance between the architect of Constellation and the architect of Starship?
What more unlikely duo than Griffin and Musk?
Griffin and Musk were together on the trip Musk took to Russia to try to buy an old ICBM where Musk started his idea for SpaceX. Griffin also did the COTS program which saved SpaceX.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Llian Rhydderch on 07/16/2019 08:16 pm
Space Development Agency releases its first solicitation

by Sandra Erwin — July 4, 2019

The SDA is looking to develop an "agile, responsive next-generation space architecture."

https://spacenews.com/space-development-agency-releases-its-first-solicitation/ (https://spacenews.com/space-development-agency-releases-its-first-solicitation/)

Starlink for SDA
Ha!
Who hear can envision a technical bromance between the architect of Constellation and the architect of Starship?
What more unlikely duo than Griffin and Musk?
Griffin and Musk were together on the trip Musk took to Russia to try to buy an old ICBM where Musk started his idea for SpaceX. Griffin also did the COTS program which saved SpaceX.

And Griffin was also one of the ~20 or so persons hired by Elon Musk (on consulting arrangements) before he started SpaceX to advise him on that prospect.  They formed a sort of "kitchen cabinet" that met approximately weekly in Silicon Valley to investigate and research various issues and matters related to pottentially forming a private rocket company.  Then, they would each go off and work on assignments for the next week. 

At the end of the time of a few months doing this, Musk went around the table and asked each one, individually, should I form a rocket company.  I've heard from two of the 20 personally that all but one of the ~20 members said "no", and only one said a qualified yes.  Elon obviously took that info in; then chose to create Space Exploration Technologies in 2002. 

The rest is history.

Griffin was one of those who said no.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 08/06/2019 08:59 pm
[I don't remember seeing this posted.  NSF is still working on coordination with OneWeb, Kepler, etc.]

Statement on NSF and SpaceX Radio Spectrum Coordination Agreement (https://www.nsf.gov/news/news_summ.jsp?cntn_id=298678)

June 4, 2019

In late May, SpaceX launched its first 60 Starlink satellites into orbit. SpaceX plans to launch a much larger satellite constellation into low-Earth orbit with the goal of providing terrestrial internet service. The operation of these satellites will utilize frequencies that neighbor some radio astronomy assets in the 10.6 - 10.7 GHz band. SpaceX coordinated with NSF and its radio astronomy observatories regarding potential interference from their use of the radio spectrum. After working closely with SpaceX, NSF has finalized a coordination agreement to ensure the company’s Starlink satellite network plans will meet international radio astronomy protection standards, limiting interference in this radio astronomy band. Additionally, NSF and SpaceX will continue to explore methods to further protect radio astronomy. Together we are setting the stage for a successful partnership between commercial and public endeavors that allows important science research to flourish alongside satellite communication.

-NSF-
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 08/07/2019 03:24 am
1460-EX-ST-2019 (https://apps.fcc.gov/oetcf/els/reports/STA_Print.cfm?mode=current&application_seq=94143&RequestTimeout=1000)
Ka-band ground station testing in McGregor, that's a good sign.
Quote
Please explain in the area below why an STA is necessary:
This STA is necessary to authorize testing of Ka-band gateway antennas used to route broadband traffic over the Starlink satellite system.

Purpose of Operation
Please explain the purpose of operation:    The purpose of the operation is for EMI testing across the Ka-band spectrum. This is a brief test, and EIRP is not expected to surpass 61.6 dBW.
Title: Re: Starlink : General Discussion - Thread 2
Post by: docmordrid on 08/07/2019 07:07 pm
Yup, DoD is happy with StarLink.

Quote
Eric Berger @ScuGuySpace (Ars Technica)

...the Space and Missile Symposium in Northern Alabama is hardly where I'd expect a SpaceX love fest to break out.

Eric Berger ✔ @SciGuySpace
This comment about SpaceX and Starlink is remarkable due to A) the location in Huntsville, AL; and B) by an AF General, Terrence O'Shaughnessy:

"Completely changed our ability" to sense threats. "Holy smokes. Talk about being able to move the ball."
|
Top general says SpaceX may have just changed space defense

The general in charge of defending America from attacks from space says SpaceX's launch of 60 satellites with one rocket is a major breakthrough.

Link... (https://www.al.com/news/huntsville/2019/08/top-general-says-spacex-may-have-just-changed-space-defense.html?outputType=amp)

|
Eric Berger ✔ @SciGuySpace
More: O'Shaughnessy, who commands America’s homeland defense including the NORAD warning system in Colorado, made the "holy smokes" remark responding to a question about promising new technologies asked at the annual Space & Missile Symposium in Huntsville.
|
Homer Hickam @realhomerhickam
Replying to @SciGuySpace
There is no lack of supporters of @SpaceX here in Huntsville. I don't know of any detractors. The young people working on SLS are just doing their jobs as it has been given to them to do but that doesn't keep them from applauding the marvelous advances of @elonmusk & crew.
|
Eric Berger ✔ @SciGuySpace
I take your point. Even so, the Space and Missile Symposium in Northern Alabama is hardly where I'd expect a SpaceX love fest to break out.
|
Matt Haskell @mhaskellphoto
Replying to @SciGuySpace and 3 others
Granted, but at the same time they really can't deny that at this point SpaceX has totally changed the game for them. In the words of Bob Dylan, The times they are a changin!
|
Homer Hickam @realhomerhickam
It has! But like any giant ship, especially one captained by people in DC, it takes awhile for that change to be recognized. Actually, Houston has a lot more to fear in terms of a change in business as usual because of what commercial space is doing than Huntsville
|

Twitter thread
https://twitter.com/SciGuySpace/status/1159110525348974592
Title: Re: Starlink : General Discussion - Thread 2
Post by: ThomasGadd on 08/09/2019 07:09 pm
Do we have any recent information about if the next batch of Starlink's will have inter-satellite links (ISL)? 
Arguably the most important feature of Starlink.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 08/09/2019 07:21 pm
Do we have any recent information about if the next batch of Starlink's will have inter-satellite links (ISL)? 
Arguably the most important feature of Starlink.

From what Elon said at the press conference for the launch of the test satellites, I would not expect ISL anytime soon.  One of their fairly recent FCC filings mentioned work on ISL and didn't sound like they were imminent.
Title: Re: Starlink : General Discussion - Thread 2
Post by: ThomasGadd on 08/09/2019 07:39 pm
Do we have any recent information about if the next batch of Starlink's will have inter-satellite links (ISL)? 
Arguably the most important feature of Starlink.

From what Elon said at the press conference for the launch of the test satellites, I would not expect ISL anytime soon.  One of their fairly recent FCC filings mentioned work on ISL and didn't sound like they were imminent.
I suspect they'll keep it close until ready... thanks.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Roy_H on 08/09/2019 10:14 pm
Do we have any recent information about if the next batch of Starlink's will have inter-satellite links (ISL)? 
Arguably the most important feature of Starlink.

I thought that was the difference between v0.9 and v1.0. And I see the next launch labeled as v1.0. Doesn't make sense to me to put too many satellites up without inter-satellite communication. I would have thought that Starlink launches would be delayed as long as necessary until inter-satellite links were ready.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 08/09/2019 10:18 pm
Do we have any recent information about if the next batch of Starlink's will have inter-satellite links (ISL)? 
Arguably the most important feature of Starlink.

I thought that was the difference between v0.9 and v1.0. And I see the next launch labeled as v1.0. Doesn't make sense to me to put too many satellites up without inter-satellite communication. I would have thought that Starlink launches would be delayed as long as necessary until inter-satellite links were ready.

Nope.  v1.0 is supposed to add the Ka-band payload.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Keldor on 08/09/2019 11:07 pm
Do we have any recent information about if the next batch of Starlink's will have inter-satellite links (ISL)? 
Arguably the most important feature of Starlink.

I thought that was the difference between v0.9 and v1.0. And I see the next launch labeled as v1.0. Doesn't make sense to me to put too many satellites up without inter-satellite communication. I would have thought that Starlink launches would be delayed as long as necessary until inter-satellite links were ready.

Nope.  v1.0 is supposed to add the Ka-band payload.

Inter-satellite links only make sense when there are enough satellites up there to form a high bandwidth backbone.  Until then, it's better to relay the signal to a ground station and use the ordinary internet backbone after the initial hop from a customer.

It's even possible we won't see dedicated inter-satellite communication until v2.0.  It's not really that important, since they're probably perfectly capable of communicating with the same radio equipment they use to talk to the ground if needed, such as when talking to an airplane flying across the Pacific.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Roy_H on 08/09/2019 11:13 pm
Does anybody know if the next satellites will have black anodized frames to reduce reflected sunlight? Or some other variation like black paint.
Title: Re: Starlink : General Discussion - Thread 2
Post by: meekGee on 08/09/2019 11:31 pm
Do we have any recent information about if the next batch of Starlink's will have inter-satellite links (ISL)? 
Arguably the most important feature of Starlink.

I thought that was the difference between v0.9 and v1.0. And I see the next launch labeled as v1.0. Doesn't make sense to me to put too many satellites up without inter-satellite communication. I would have thought that Starlink launches would be delayed as long as necessary until inter-satellite links were ready.

Nope.  v1.0 is supposed to add the Ka-band payload.

Inter-satellite links only make sense when there are enough satellites up there to form a high bandwidth backbone.  Until then, it's better to relay the signal to a ground station and use the ordinary internet backbone after the initial hop from a customer.

It's even possible we won't see dedicated inter-satellite communication until v2.0.  It's not really that important, since they're probably perfectly capable of communicating with the same radio equipment they use to talk to the ground if needed, such as when talking to an airplane flying across the Pacific.
Right, but you can't add the links only after there are many satellites up there...

The number of satellites with ISL will by necessity start out at zero.
Title: Re: Starlink : General Discussion - Thread 2
Post by: ThomasGadd on 08/10/2019 12:18 am
Do we have any recent information about if the next batch of Starlink's will have inter-satellite links (ISL)? 
Arguably the most important feature of Starlink.

I thought that was the difference between v0.9 and v1.0. And I see the next launch labeled as v1.0. Doesn't make sense to me to put too many satellites up without inter-satellite communication. I would have thought that Starlink launches would be delayed as long as necessary until inter-satellite links were ready.

Nope.  v1.0 is supposed to add the Ka-band payload.

Inter-satellite links only make sense when there are enough satellites up there to form a high bandwidth backbone.  Until then, it's better to relay the signal to a ground station and use the ordinary internet backbone after the initial hop from a customer.

It's even possible we won't see dedicated inter-satellite communication until v2.0.  It's not really that important, since they're probably perfectly capable of communicating with the same radio equipment they use to talk to the ground if needed, such as when talking to an airplane flying across the Pacific.

Satellites without ISL's take more satellites and ground infrastructure just to be visible because they limited to earth-satellite-earth line of sight. 
I haven't figured out the minimum satellites but it would be based on the visibility to the 5 ground stations. 

If they have ISL's they can relay from satellite to satellite until reaching a ground station. 

At 550 km it takes 11 per plane for 1 to be visible from the ground, Spacex has decide to do the U.S. first so that is 6 planes. 

The theoretical minimum satellites would be 11*6=60.  Not production, no spares or redundancy. 
Adding by 11 per plane with extras as spares adds redundancy and parallel routes. 
Title: Re: Starlink : General Discussion - Thread 2
Post by: meekGee on 08/10/2019 12:49 am
I think the right answer is that they need ISL asap, but will launch what they can since having many in orbit is hugely instructive, and they can take advantage of their very low internal launch costs.
Title: Re: Starlink : General Discussion - Thread 2
Post by: OTV Booster on 08/10/2019 11:26 pm
I think the right answer is that they need ISL asap, but will launch what they can since having many in orbit is hugely instructive, and they can take advantage of their very low internal launch costs.


I expect they are still working out a lot on the protocols and sundry, and are spoofing ISL via ground stations. Can’t do much with timing but a lot can be played with. That and staking out marketing territory and showing progress towards meeting final licensing requirements. Probably none of the current and soon to come items are really expected to be part of the first live on line revenue generating constellation.


Since when did SX version numbers line up in any consistent way?


Phil
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 08/10/2019 11:30 pm
Elon said the initial constellation wouldn't have ISL.  I'm not entirely sure how many satellites the initial constellation is, but that would imply at least 400 sats without ISL, and I bet it's a lot more than that.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Semmel on 08/11/2019 10:17 pm
Elon said the initial constellation wouldn't have ISL.  I'm not entirely sure how many satellites the initial constellation is, but that would imply at least 400 sats without ISL, and I bet it's a lot more than that.

I remember it differently. I thought Shotwell said the test satellites that are currently in orbit dont have ISL but that the production version does have it. We will see with the next two launches which version is real.
Title: Re: Starlink : General Discussion - Thread 2
Post by: oldAtlas_Eguy on 08/11/2019 10:52 pm
Here is an item that will be a significant milestone and that is probably by the EOY 2019 SpaceX will have significantly more than 100 operational sats on orbit. This will be the largest constellation and will continue to set size records almost monthly.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 08/12/2019 01:49 am
Elon said the initial constellation won't have intersatellite links.  There was nothing ambiguous about it (other than exactly how many satellites he considers to be the initial constellation), and that's the most recent info we have.  You can choose to believe otherwise if you want to.  ¯\_(ツ)_/¯
Title: Re: Starlink : General Discussion - Thread 2
Post by: ThomasGadd on 08/12/2019 02:43 am
Elon said the initial constellation won't have intersatellite links.  There was nothing ambiguous about it (other than exactly how many satellites he considers to be the initial constellation), and that's the most recent info we have.  You can choose to believe otherwise if you want to.  ¯\_(ツ)_/¯
You do answer this question a lot... it probably be a relief when you can say something else...
Title: Re: Starlink : General Discussion - Thread 2
Post by: oldAtlas_Eguy on 08/12/2019 05:07 am
Elon said the initial constellation won't have intersatellite links.  There was nothing ambiguous about it (other than exactly how many satellites he considers to be the initial constellation), and that's the most recent info we have.  You can choose to believe otherwise if you want to.  ¯\_(ツ)_/¯
You do answer this question a lot... it probably be a relief when you can say something else...
I think the answer to how big is the initial constellation is embedded in the wording on initial launches of 6 or 6 more launches (7 including the first) for a constellation size of <420. But there was also wording about 12 launches to get to initial operations. So the value here could be 400 or 800. But likely is the 800 value that is being referenced. Which puts no ISL until late 2020 or early 2021. If Starship goes operational in mid late 2021 the ISL being added may occur in the upgrade to V2 for launch on Starship.
Title: Re: Starlink : General Discussion - Thread 2
Post by: freddo411 on 08/12/2019 05:42 am
Anyone hazard a guess as to why ISL, of some sort, hasn't' been integrated on the first batches of SL sats?   

My wild guess is that the optics that would be used in the lasers would survive reentry;   and SX would like the satellites to be fully disposable upon deorbit.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 08/12/2019 01:23 pm
Anyone hazard a guess as to why ISL, of some sort, hasn't' been integrated on the first batches of SL sats?   

My wild guess is that the optics that would be used in the lasers would survive reentry;   and SX would like the satellites to be fully disposable upon deorbit.

My guess is they haven't gotten the price and performance to their liking yet.  They've had a lot of technologies to work on for these sats.  The major components seem to be designed and built in-house.  Optical inter-satellite links are not a common technology yet and I doubt the market price would be palatable for SpaceX.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Nomadd on 08/12/2019 03:24 pm
 Globalstar had one advantage over Iridium. They had higher quality audio because they didn't cram it into a 2400 bps channel. But Iridium had one huge advantage, and that was the ISLs. Without them you lose a lot of the globe, you lose the time and distance advantages and you have to have many more ground stations.
 I've wondered if the sats have to be so high in the sky because of PA antenna angle limitations. Or, if a four antenna system might be able to work with sats at a much lower angle to increase the number they can see in the early days.
Title: Re: Starlink : General Discussion - Thread 2
Post by: speedevil on 08/12/2019 03:40 pm
I've wondered if the sats have to be so high in the sky because of PA antenna angle limitations. Or, if a four antenna system might be able to work with sats at a much lower angle to increase the number they can see in the early days.
Starlink goes (from memory) down to 25 degrees from the horizon.
Once you start pushing this, you also end up with range issues - 15 degrees over the horizon is quite a lot further away, meaning your performance in all aspects (bitrate/noise margin, cell spot size, ...) goes down.
Also, you start going through way, way more air and weather, which all attenuate the signal - especially in the worst case.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Nomadd on 08/12/2019 03:55 pm
I've wondered if the sats have to be so high in the sky because of PA antenna angle limitations. Or, if a four antenna system might be able to work with sats at a much lower angle to increase the number they can see in the early days.
Starlink goes (from memory) down to 25 degrees from the horizon.
Once you start pushing this, you also end up with range issues - 15 degrees over the horizon is quite a lot further away, meaning your performance in all aspects (bitrate/noise margin, cell spot size, ...) goes down.
Also, you start going through way, way more air and weather, which all attenuate the signal - especially in the worst case.
Part of the four antenna system would be higher gain to make up for the distance, and in good weather, the extra distance through the air isn't as bad as you might think. We'd go down to five degrees or less at sea without much signal loss in clear skies.
 Not having any real antenna specs on either end, it's hard to know how much margin they're putting in.
Title: Re: Starlink : General Discussion - Thread 2
Post by: speedevil on 08/12/2019 04:00 pm
I've wondered if the sats have to be so high in the sky because of PA antenna angle limitations. Or, if a four antenna system might be able to work with sats at a much lower angle to increase the number they can see in the early days.
Starlink goes (from memory) down to 25 degrees from the horizon.
Once you start pushing this, you also end up with range issues - 15 degrees over the horizon is quite a lot further away, meaning your performance in all aspects (bitrate/noise margin, cell spot size, ...) goes down.
Also, you start going through way, way more air and weather, which all attenuate the signal - especially in the worst case.
Part of the four antenna system would be higher gain to make up for the distance, and in good weather, the extra distance through the air isn't as bad as you might think. We'd go down to five degrees or less at sea without much signal loss in clear skies.
 Not having any real antenna specs on either end, it's hard to know how much margin they're putting in.

And obviously, to a degree, sometimes you don't care about performance.
If you are doing this for residual capacity over very sparsely populated areas, the fact you can't cope with the same number of customers may be an utter non-issue.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 08/12/2019 04:02 pm
Quote
To maintain suitable coverage during the very early stages of initial deployment,
SpaceX may periodically use a minimum elevation angle as low as 25 degrees for this initial shell.
Then, as further satellites are deployed to populate the remainder of the constellation, SpaceX will
revert to a 40 degree minimum elevation angle for all user and gateway beams.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Nomadd on 08/12/2019 04:48 pm
Quote
To maintain suitable coverage during the very early stages of initial deployment,
SpaceX may periodically use a minimum elevation angle as low as 25 degrees for this initial shell.
Then, as further satellites are deployed to populate the remainder of the constellation, SpaceX will
revert to a 40 degree minimum elevation angle for all user and gateway beams.
I assume the ground antenna design will change when that happens. Older ones would still work, but newer ones could be a little smaller or better performing since they wouldn't have to cover 130 degrees of sky.
 I wonder if you'll be able to program in blockages so you won't get assigned a sat that's about to go behind a building. Ku band dishes on ships can already do that for turns, so you can do an orderly handoff instead of just getting the signal cutoff without warning. Of course, their sats aren't zipping across the sky at 14,000 mph.
Title: Re: Starlink : General Discussion - Thread 2
Post by: cuddihy on 08/13/2019 03:07 pm

 I wonder if you'll be able to program in blockages so you won't get assigned a sat that's about to go behind a building. Ku band dishes on ships can already do that for turns, so you can do an orderly handoff instead of just getting the signal cutoff without warning. Of course, their sats aren't zipping across the sky at 14,000 mph.

By the same token that proves this is a fairly *solved* problem. If a modern maritime 1-2M dish tracking a fixed GSO sat can handle 15 degree pitch & rolls from weather, a satellite moving with a much slower angular rate across the sky is not hard.

Smartphone-level GPS /IMUs take care of terminal orientation & location. Ephemeris & software calculate blockage after 5-7 satellites have  linked / blocked at different locations. You can build an angular access "map" for the terminal quickly from known ephemeris.

Title: Re: Starlink : General Discussion - Thread 2
Post by: ThomasGadd on 08/14/2019 04:16 pm
The first Starlink mission was volume limited. 
If they build or buy the new, taller fairing for NSSL missions they could use Starlink to validate the fairing.  The fairing will be heavier and more expensive than the standard F9 fairing. 
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 08/14/2019 04:18 pm
The first Starlink mission was volume limited. 
If they build or buy the new, taller fairing for NSSL missions they could use Starlink to validate the fairing.  The fairing will be heavier and more expensive than the standard F9 fairing.

Why do you think it was volume limited?  I don't think that's true.
Title: Re: Starlink : General Discussion - Thread 2
Post by: intelati on 08/14/2019 04:31 pm
The first Starlink mission was volume limited. 
If they build or buy the new, taller fairing for NSSL missions they could use Starlink to validate the fairing.  The fairing will be heavier and more expensive than the standard F9 fairing.

Why do you think it was volume limited?  I don't think that's true.

Actually, if anything, we have evidence that it was actually mass limited. I forget if that was privileged information, but certainly in the webcast, you saw the HOT re-entry of the booster. (Thus implying a heavy payload.)
Title: Re: Starlink : General Discussion - Thread 2
Post by: ThomasGadd on 08/14/2019 04:36 pm
The first Starlink mission was volume limited. 
If they build or buy the new, taller fairing for NSSL missions they could use Starlink to validate the fairing.  The fairing will be heavier and more expensive than the standard F9 fairing.

Why do you think it was volume limited?  I don't think that's true.
Looking for the Musk quote...  Never mind

Isn't Starlink a good thing to use to validate the new fairing?
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 08/14/2019 04:44 pm
It depends on the details of the large fairing (and the guy on Twitter retracted his statement from yesterday).  If it's an outsourced fairing that is expensive and maybe not amenable to SpaceX's normal processing flow then I don't think it would make any sense for Starlink.  If SpaceX is serious about moving to StarShip then a large fairing might only be to support their Air Force business.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Unrulycow on 08/14/2019 04:48 pm
The first Starlink mission was volume limited. 
If they build or buy the new, taller fairing for NSSL missions they could use Starlink to validate the fairing.  The fairing will be heavier and more expensive than the standard F9 fairing.

Why do you think it was volume limited?  I don't think that's true.

Actually, if anything, we have evidence that it was actually mass limited. I forget if that was privileged information, but certainly in the webcast, you saw the HOT re-entry of the booster. (Thus implying a heavy payload.)
It was the heaviest payload they've ever launched, and near the limit of what they can lift in reusable config. It was also pretty cramped in the fairing, so it was both mass and volume limited. If they used the bigger fairing to launch more sats, they would need to launch on Falcon Heavy.
Title: Re: Starlink : General Discussion - Thread 2
Post by: dglow on 08/14/2019 04:59 pm
The first Starlink mission was volume limited. 
If they build or buy the new, taller fairing for NSSL missions they could use Starlink to validate the fairing.  The fairing will be heavier and more expensive than the standard F9 fairing.

Why do you think it was volume limited?  I don't think that's true.

Actually, if anything, we have evidence that it was actually mass limited. I forget if that was privileged information, but certainly in the webcast, you saw the HOT re-entry of the booster. (Thus implying a heavy payload.)
It was the heaviest payload they've ever launched, and near the limit of what they can lift in reusable config. It was also pretty cramped in the fairing, so it was both mass and volume limited. If they used the bigger fairing to launch more sats, they would need to launch on Falcon Heavy.

Yes. And in the NSSL context Falcon Heavy is the only vehicle that would ever launch the larger, RUAG-supplied fairing.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Kragrathea on 08/17/2019 03:21 am
I drive by SpaceX Starlink in Redmond from time to time. I noticed that the lot next to them has been cleared and they are throwing up a building or two extra fast. I strongly suspect this is going to be new Starlink manufacturing space.

https://goo.gl/maps/kX3n1vrx8QMnPamx6

I'll get some pics next time I go by. Nothing much to see so far.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Lar on 08/19/2019 02:18 pm
I drive by SpaceX Starlink in Redmond from time to time. I noticed that the lot next to them has been cleared and they are throwing up a building or two extra fast. I strongly suspect this is going to be new Starlink manufacturing space.

https://goo.gl/maps/kX3n1vrx8QMnPamx6

I'll get some pics next time I go by. Nothing much to see so far.
I went to the map link but I wasn't able to tell which direction to look for the clearing you speak of
Title: Re: Starlink : General Discussion - Thread 2
Post by: RedLineTrain on 08/19/2019 02:33 pm
I drive by SpaceX Starlink in Redmond from time to time. I noticed that the lot next to them has been cleared and they are throwing up a building or two extra fast. I strongly suspect this is going to be new Starlink manufacturing space.

https://goo.gl/maps/kX3n1vrx8QMnPamx6

I'll get some pics next time I go by. Nothing much to see so far.

Is the whole lot being cleared or a portion?

Thank you for passing this information along.  SpaceX is building a nice-sized campus on that block.
Title: Re: Starlink : General Discussion - Thread 2
Post by: AC in NC on 08/19/2019 05:06 pm
I drive by SpaceX Starlink in Redmond from time to time. I noticed that the lot next to them has been cleared and they are throwing up a building or two extra fast. I strongly suspect this is going to be new Starlink manufacturing space.

https://goo.gl/maps/kX3n1vrx8QMnPamx6

I'll get some pics next time I go by. Nothing much to see so far.
I went to the map link but I wasn't able to tell which direction to look for the clearing you speak of

I agree with the ambiguity absent a note from the locals.  I tend to assume it's the "Island of Trees" across the road from the existing SpaceX location but the clearing to the ENE makes it unclear.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Roy_H on 08/20/2019 05:24 am
I drive by SpaceX Starlink in Redmond from time to time. I noticed that the lot next to them has been cleared and they are throwing up a building or two extra fast. I strongly suspect this is going to be new Starlink manufacturing space.

https://goo.gl/maps/kX3n1vrx8QMnPamx6

I'll get some pics next time I go by. Nothing much to see so far.
I went to the map link but I wasn't able to tell which direction to look for the clearing you speak of

I agree with the ambiguity absent a note from the locals.  I tend to assume it's the "Island of Trees" across the road from the existing SpaceX location but the clearing to the ENE makes it unclear.

Seem obvious to me. When you first click on the map link you are zoomed in to the "island of trees". What could be clearer. As Google maps are rarely so recent as to be just days old, cleared areas outside of the area in question likely pre-date this observation by Kragrathea.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Kragrathea on 08/20/2019 08:42 am
Yes, that entire area of trees next to Marketplace Dr has been cleared.

SpaceX also has the 2 unmarked buildings on the right side of the screen in that map shot. And the parking lot on the other side of Marketplace is SpaceX only. That's part of why I think it is SpaceX they are clearing the lot for. Their employees have been crossing it to park.
Title: Re: Starlink : General Discussion - Thread 2
Post by: DaveGee66 on 08/20/2019 02:48 pm
I drive by SpaceX Starlink in Redmond from time to time. I noticed that the lot next to them has been cleared and they are throwing up a building or two extra fast. I strongly suspect this is going to be new Starlink manufacturing space.

https://goo.gl/maps/kX3n1vrx8QMnPamx6

I'll get some pics next time I go by. Nothing much to see so far.
I went to the map link but I wasn't able to tell which direction to look for the clearing you speak of

I agree with the ambiguity absent a note from the locals.  I tend to assume it's the "Island of Trees" across the road from the existing SpaceX location but the clearing to the ENE makes it unclear.

Seem obvious to me. When you first click on the map link you are zoomed in to the "island of trees". What could be clearer. As Google maps are rarely so recent as to be just days old, cleared areas outside of the area in question likely pre-date this observation by Kragrathea.

Yes the sat maps from google are usually 'out of date' (1st world problems for sure) a trick I use (provided a public road is available) is to 'drive around' the area using the google street view cams... they are MUCH more 'up to date'...  then again sometimes not but I just checked and from the street view and no such luck photos are all showing the trees up / no construction. :(
Title: Re: Starlink : General Discussion - Thread 2
Post by: aero on 08/20/2019 03:58 pm
Quote
Yes the sat maps from google are usually 'out of date' (1st world problems for sure) a trick I use (provided a public road is available) is to 'drive around' the area using the google street view cams... they are MUCH more 'up to date'...  then again sometimes not but I just checked and from the street view and no such luck photos are all showing the trees up / no construction.

Well, it's pretty obvious that we'll just have to wait until the Starlink constellation is operating, then (if Musk adds cameras) we can look for the site in real-time!

And by the way, have we anywhere focused on the benefits that camera bearing Starlink satellites could enable? I know that we've hit on some of them in passing but  I don't believe I've seen worldwide, real-time Earth observations mentioned anywhere. Of course, law enforcement comes high on the list of beneficiaries. Imagine having an aerial overview of the disaster scene at the same time as units are being dispatched to that scene. And how about search and rescue? Hiker's emergency kits could contain a sign (here I am) or the material to make the sign to mark their location when they get lost. (Or a cell phone!)
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 08/20/2019 04:14 pm
And by the way, have we anywhere focused on the benefits that camera bearing Starlink satellites could enable?

What resolution are you looking to get, and would the equipment to get that resolution easily fit into the current form of the satellites?
Title: Re: Starlink : General Discussion - Thread 2
Post by: RedLineTrain on 08/20/2019 05:48 pm
Yes, that entire area of trees next to Marketplace Dr has been cleared.

SpaceX also has the 2 unmarked buildings on the right side of the screen in that map shot. And the parking lot on the other side of Marketplace is SpaceX only. That's part of why I think it is SpaceX they are clearing the lot for. Their employees have been crossing it to park.

Sounds reasonable.  Judging from LinkedIn, it appears that SpaceX is once again growing Seattle headcount.

I also think SpaceX has part of 22908 NE Adler Crest Dr.  Or at least, at one time they did.  King County no longer has permitting activity online, so it is a little more difficult to tell what is happening.  King County does provide information to the public upon request, but I have not submitted one.
Title: Re: Starlink : General Discussion - Thread 2
Post by: aero on 08/21/2019 01:04 am
And by the way, have we anywhere focused on the benefits that camera bearing Starlink satellites could enable?

What resolution are you looking to get, and would the equipment to get that resolution easily fit into the current form of the satellites?

I really don't know the answer to that question, instead, I would take a different approach. I would ask, "What size camera equipment could they fit on a Starlink satellite and what benefit could be derived from that real-time Earth observation capability?"
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 08/21/2019 01:08 am
And by the way, have we anywhere focused on the benefits that camera bearing Starlink satellites could enable?

What resolution are you looking to get, and would the equipment to get that resolution easily fit into the current form of the satellites?

I really don't know the answer to that question, instead, I would take a different approach. I would ask, "What size camera equipment could they fit on a Starlink satellite and what benefit could be derived from that real-time Earth observation capability?"

That might be a good topic for a new thread.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Kragrathea on 08/21/2019 03:14 am
Here are a few drone shots of the SpaceX offices in Redmond with the new construction visible.

And the public notice for the new construction.

And a drone shot of the ground station in North Bend WA.

And for comparison, a shot of the Conrad MT ground station I took in May.

Quite a collection. 

Edit: Based on the permit number I found the construction companies page on the project. No mention of the client that I can see.
http://www.sierraind.com/new-project-redmond-ridge-113/
Title: Re: Starlink : General Discussion - Thread 2
Post by: RDMM2081 on 08/22/2019 12:21 am
What is the current consensustimate (made up words sorry) for the production rate of Starlink satellites?

Given that 60 satellites launched on May 23 (89 days ago), but really, they were all at launch site and encapsulated some time before that.  This should be somewhere around 100 days since the last production batch.  Even if they are only averaging 1 satellite every 2 days, they should be very close to another full batch of 60 by now.

Falcon 9 manifest thread (https://forum.nasaspaceflight.com/index.php?topic=43418.0) estimates that the launch date for the v1 satellites to be mid-October, but the second launch of v1 only two weeks after that, November 4th.  This would be approximately 165 days since the first launch and assuming they keep the number of satellites per launch the same, 120 satellites in 165 days is getting very close to 1 per day.  I would guess that by early November the satellites should be coming off the line at least one per day.

That seems pretty cool to me but I'm mostly just guessing, anyone have any better thoughts or info?
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 08/22/2019 12:37 am
I would guess their peak rate is already at least one per day, but they probably haven't been running continuously as they started manufacturing the full production design (with Ka-band) and addressed failures from the set of test sats.
Title: Re: Starlink : General Discussion - Thread 2
Post by: aero on 08/22/2019 12:41 am
How many satellites do they need and how many days do they have to get them on orbit, divide.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Lar on 08/22/2019 12:56 am
I expect to see a steep ramp up when the design changes less. I expect this next launch is still going to be working bugs out and testing things. But there's some merit in ramping up just to ramp up, for the learning, even if what you're making isn't quite right. I bet they are well past 1 a day now. End state I think the rate is going to be more like one every 3.5 hours (2500 a year is 6.8ish a day) if you are producing 24/7 .. or one every 40 minutes or so if you are assuming 5 day / 8 hours a day with some time off for holidays...
Title: Re: Starlink : General Discussion - Thread 2
Post by: aero on 08/22/2019 01:17 am
I expect to see a steep ramp up when the design changes less. I expect this next launch is still going to be working bugs out and testing things. But there's some merit in ramping up just to ramp up, for the learning, even if what you're making isn't quite right. I bet they are well past 1 a day now. End state I think the rate is going to be more like one every 3.5 hours (2500 a year is 6.8ish a day) if you are producing 24/7 .. or one every 40 minutes or so if you are assuming 5 day / 8 hours a day with some time off for holidays...

Of course, SpaceX isn't timid when asking for more hours from the labor force. There are 128 hours more hours in a week than just the 40 hour workweek.
Title: Re: Starlink : General Discussion - Thread 2
Post by: wannamoonbase on 08/22/2019 04:32 am
I expect to see a steep ramp up when the design changes less. I expect this next launch is still going to be working bugs out and testing things. But there's some merit in ramping up just to ramp up, for the learning, even if what you're making isn't quite right. I bet they are well past 1 a day now. End state I think the rate is going to be more like one every 3.5 hours (2500 a year is 6.8ish a day) if you are producing 24/7 .. or one every 40 minutes or so if you are assuming 5 day / 8 hours a day with some time off for holidays...

At that rate you almost want the production line at the Cape and feeding into the F9 processing facility.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Zed_Noir on 08/22/2019 03:47 pm
Anyone know how much of the manufacturing for the current Starlink satellite can be automated? Musk have Tesla Grohmann automation to call upon for setting up automated production lines.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Lar on 08/22/2019 04:45 pm
I expect to see a steep ramp up when the design changes less. I expect this next launch is still going to be working bugs out and testing things. But there's some merit in ramping up just to ramp up, for the learning, even if what you're making isn't quite right. I bet they are well past 1 a day now. End state I think the rate is going to be more like one every 3.5 hours (2500 a year is 6.8ish a day) if you are producing 24/7 .. or one every 40 minutes or so if you are assuming 5 day / 8 hours a day with some time off for holidays...

At that rate you almost want the production line at the Cape and feeding into the F9 processing facility.
They seem to be ramping up where they are now. I suspect moving would be highly disruptive. The distance from the factory for something that fits within a standard semi trailer envelope (cube and weight) isn't that big a deal, I don't think. yes it adds lag but... not insurmountably so.   
Title: Re: Starlink : General Discussion - Thread 2
Post by: Asteroza on 08/22/2019 11:54 pm
Anyone know how much of the manufacturing for the current Starlink satellite can be automated? Musk have Tesla Grohmann automation to call upon for setting up automated production lines.

Looking at OneWeb's manufacturing line, it isn't that heavily automated, but has some automation due to the quantities involved. Even at Starlink's pace, you don't need Tesla levels of automation.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Kragrathea on 08/24/2019 09:42 pm
From twitter:

https://twitter.com/Megaconstellati/status/1164206179935019008

Quote
Following @SpaceX's request from 16 April for 6 Ku band gateways for #Starlink on 15 Aug the firm has filed 2 additional license requests with the @FCC for two Ka band gateways located at: 📡Conrad, MT (48.203306,-111.945278), dual band (Ku/Ka) 📡Loring, ME (46.914917,-67.919528)


I guess they are just upgrading the one in Conrad with Ka band.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 08/24/2019 09:47 pm
SpaceX filed another extension request (http://licensing.fcc.gov/cgi-bin/ws.exe/prod/ib/forms/reports/swr031b.hts?q_set=V_SITE_ANTENNA_FREQ.file_numberC/File+Number/%3D/SATSTA2019081500075&prepare=&column=V_SITE_ANTENNA_FREQ.file_numberC/File+Number) for their Ku-band earth stations since they are still operating under STA.

SpaceX also filed their first couple applications for Ka-band gateways (it says they will have at least five).  They will have eight 1.5m antennas at each site.  The first two filed are for Conrad, Montana (SES-LIC-INTR2019-03001 (http://licensing.fcc.gov/cgi-bin/ws.exe/prod/ib/forms/reports/swr031b.hts?q_set=V_SITE_ANTENNA_FREQ.file_numberC/File+Number/%3D/SESLICINTR201903001&prepare=&column=V_SITE_ANTENNA_FREQ.file_numberC/File+Number)) and Loring, Maine (SES-LIC-INTR2019-03002 (http://licensing.fcc.gov/cgi-bin/ws.exe/prod/ib/forms/reports/swr031b.hts?q_set=V_SITE_ANTENNA_FREQ.file_numberC/File+Number/%3D/SESLICINTR201903002&prepare=&column=V_SITE_ANTENNA_FREQ.file_numberC/File+Number)).  The Coordination Report file has info on the antennas.

Attached the description document to the post in the other thread.
Title: Re: Starlink : General Discussion - Thread 2
Post by: niwax on 08/29/2019 01:32 am
In other news, 9 planned Starlink launches next year, monthly cadence with presumably final sats starting in April.

The mid-incination opportunities I suppose are starlink launches...

https://www.spacex.com/smallsat

edit:

It spells it out:
Quote
SpaceX's Starlink missions will also provide monthly launch opportunities starting in 2020.

With 60 sats per launch, that would give 1320 in orbit by end of 2021.
Title: Re: Starlink : General Discussion - Thread 2
Post by: PM3 on 08/29/2019 01:46 am
In other news, 9 planned Starlink launches next year, monthly cadence with presumably final sats starting in April.

The mid-incination opportunities I suppose are starlink launches...

https://www.spacex.com/smallsat

edit:

It spells it out:
Quote
SpaceX's Starlink missions will also provide monthly launch opportunities starting in 2020.

With 60 sats per launch, that would give 1320 in orbit by end of 2021.

9 Starlink launches with rideshare opportunites next year, starting in April. There may be more launches before, but not with the technical capability for rideshare.

How to mount 3rd party satellites on a Starlink stack?  ??? Or are we already talking about Starship here?
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 08/29/2019 01:51 am
60 is max Starlink sats per launch, could be less.

Rideshares should be ESPA ring at bottom of stack (will need to be a strong ring).
Title: Re: Starlink : General Discussion - Thread 2
Post by: Zed_Noir on 08/29/2019 06:00 am
60 is max Starlink sats per launch, could be less.

Rideshares should be ESPA ring at bottom of stack (will need to be a strong ring).

You could convert Starlink spacecraft to cubesat dispenser. And stacked as many as customer demand need along with the regular Starlink spacecrafts. Converted Starlink spacecraft have the bonus features of propulsion, attitude control and solar power generation.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Confusador on 08/29/2019 12:08 pm
60 is max Starlink sats per launch, could be less.

Rideshares should be ESPA ring at bottom of stack (will need to be a strong ring).

You could convert Starlink spacecraft to cubesat dispenser. And stacked as many as customer demand need along with the regular Starlink spacecrafts. Converted Starlink spacecraft have the bonus features of propulsion, attitude control and solar power generation.

Maybe they could convert a Starlink sat to a dispenser, but they're not going to yet.  They were explicit about requiring an ESPA connector in the rideshare announcement, and suggested that you could use it to send your own cubesat deployer.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Zed_Noir on 08/29/2019 02:32 pm
60 is max Starlink sats per launch, could be less.

Rideshares should be ESPA ring at bottom of stack (will need to be a strong ring).

You could convert Starlink spacecraft to cubesat dispenser. And stacked as many as customer demand need along with the regular Starlink spacecrafts. Converted Starlink spacecraft have the bonus features of propulsion, attitude control and solar power generation.

Maybe they could convert a Starlink sat to a dispenser, but they're not going to yet.  They were explicit about requiring an ESPA connector in the rideshare announcement, and suggested that you could use it to send your own cubesat deployer.

To clarified. The SpaceX rideshare proposal appears to be tailored for smallsats which definitely require a ESPA connector.

My take on a Starlink spacecraft cubesat dispenser variant is that you could simply stacked one with any Starlink launch with the other flatpack spacecrafts. Which give SpaceX a lot more launch slots for anyone with a cubesat looking for a ride in addition to the dedicated rideshare flights.

Also the Starlink spacecraft is big enough to mounted almost any cubesat deployer from customers.
Title: Re: Starlink : General Discussion - Thread 2
Post by: groknull on 08/29/2019 04:55 pm
60 is max Starlink sats per launch, could be less.

Rideshares should be ESPA ring at bottom of stack (will need to be a strong ring).

An ESPA ring probably won't fit under a Starlink stack.  The Starlink payload attach fitting does not appear to have a standard 1575mm bolted interface, but rather a square platform for the Starlink stack.

Attached image from this post:
https://forum.nasaspaceflight.com/index.php?topic=48135.msg1945139#msg1945139
Title: Re: Starlink : General Discussion - Thread 2
Post by: Confusador on 08/29/2019 05:13 pm
60 is max Starlink sats per launch, could be less.

Rideshares should be ESPA ring at bottom of stack (will need to be a strong ring).

An ESPA ring probably won't fit under a Starlink stack.  The Starlink payload attach fitting does not appear to have a standard 1575mm bolted interface, but rather a square platform for the Starlink stack.

Attached image from this post:
https://forum.nasaspaceflight.com/index.php?topic=48135.msg1945139#msg1945139

Nothing would fit in that configuration.  I'm assuming they've redesigned the adapter to incorporate a ring below the square platform, rather than redesigning the Starlink sats to accomodate secondaries on top.
Title: Re: Starlink : General Discussion - Thread 2
Post by: OTV Booster on 08/30/2019 03:23 am
60 is max Starlink sats per launch, could be less.

Rideshares should be ESPA ring at bottom of stack (will need to be a strong ring).

An ESPA ring probably won't fit under a Starlink stack.  The Starlink payload attach fitting does not appear to have a standard 1575mm bolted interface, but rather a square platform for the Starlink stack.

Attached image from this post:
https://forum.nasaspaceflight.com/index.php?topic=48135.msg1945139#msg1945139

Nothing would fit in that configuration.  I'm assuming they've redesigned the adapter to incorporate a ring below the square platform, rather than redesigning the Starlink sats to accomodate secondaries on top.

SX is nothing but practical. If they could generate enough revenue with small sats to put a dent in launch costs they might be willing to cut the stack of star links to 50 and build enough of an adapter that the star links wouldn’t be setting directly on the paying customer.

The one launch they’ve done inserted 60 with 2 DOA. they need 66 per orbit so they must have a plan to do some roundout launches - probably with some crafty scheme using precession or something to allow one launch to service multiple orbits with minimum dV.

If their book keepers are as sharp as their engineers they probably already know what revenue the need to make an 8, 10, 12 or 14 sat cut worthwhile.

Phil
Title: Re: Starlink : General Discussion - Thread 2
Post by: FutureSpaceTourist on 09/02/2019 03:07 pm
twitter.com/esaoperations/status/1168533241873260544

Quote
For the first time ever, ESA has performed a 'collision avoidance manoeuvre' to protect one of its satellites from colliding with a 'mega constellation'
#SpaceTraffic

https://twitter.com/esaoperations/status/1168534065118679042

Quote
This morning, @ESA's #Aeolus Earth observation satellite fired its thrusters, moving it off a collision course with a @SpaceX satellite in their #Starlink constellation

twitter.com/esaoperations/status/1168534747724820482

Quote
Experts in our #SpaceDebris team calculated the risk of collision between these two active satellites, determining the safest option for #Aeolus would be to increase its altitude and pass over the @SpaceX satellite
#CollisionAvoidance

https://twitter.com/esaoperations/status/1168535780056346624

Quote
The manoeuvre took place about 1/2 an orbit before the potential collision. Not long after the collision was expected, #Aeolus called home as usual to send back its science data – proving the manoeuvre was successful and a collision was indeed avoided

twitter.com/esaoperations/status/1168536038601572353

Quote
It is very rare to perform collision avoidance manoeuvres with active satellites. The vast majority of ESA avoidance manoeuvres are the result of dead satellites or fragments from previous collisions
#SpaceDebris

https://twitter.com/esaoperations/status/1168537063316185088

Quote
In 2018, ESA performed 28 #collisionavoidance manoeuvres across its fleet. See for example a 2018 manoeuvre by @ESA_Cryosat: twitter.com/esaoperations/…

twitter.com/esaoperations/status/1168539125634482176

Quote
These avoidance manoeuvres take a lot of time to prepare - from determining the future orbital positions of all functioning spacecraft, to calculating the risk of collision and potential outcomes of different actions
📸Inside ESA's #SpaceDebris Office

https://twitter.com/esaoperations/status/1168539686819770368

Quote
As the number of satellites in orbit increases, due to 'mega constellations' such as #Starlink comprising hundreds or even thousands of satellites, today's 'manual' collision avoidance process will become impossible...
Title: Re: Starlink : General Discussion - Thread 2
Post by: soltasto on 09/02/2019 03:27 pm
Looking at the orbital parameters of Aeolus, the satellite it intercepted was 44278 aka 2019-029AV, currently in a 346km by 311km orbit (as of the last TLE), the only satellite with the perigee lower than the Aeolus mean orbital altitude, that currently is in a 314km by 308 km orbit.
Title: Re: Starlink : General Discussion - Thread 2
Post by: FutureSpaceTourist on 09/02/2019 04:51 pm
https://twitter.com/launchstuff/status/1168556819352051714

Quote
According to the latest @18SPCS orbital elements, AEOLUS would have passed within 10 km from a Starlink satellite (object 44278/2019-029AV) at 11:02:42UTC today. The relative velocity was 14.4 km/s. A collision would've been messy.
Title: Re: Starlink : General Discussion - Thread 2
Post by: ugordan on 09/02/2019 06:03 pm
Quote from: Matt Desch
Hmmm.  We move our satellites on average once a week and don't put out a press release to say who we maneuvered around...

https://twitter.com/IridiumBoss/status/1168582141128650753
Title: Re: Starlink : General Discussion - Thread 2
Post by: Mandella on 09/02/2019 06:27 pm
Quote from: Matt Desch
Hmmm.  We move our satellites on average once a week and don't put out a press release to say who we maneuvered around...

https://twitter.com/IridiumBoss/status/1168582141128650753

And thank you Matt Desch!!

I was about to post that ESA had to make something special about maneuvering around a "Mega-constellation" when adjusting orbits to miss some satellite or the other is pretty routine.
Title: Re: Starlink : General Discussion - Thread 2
Post by: woods170 on 09/02/2019 06:54 pm
Quote from: Matt Desch
Hmmm.  We move our satellites on average once a week and don't put out a press release to say who we maneuvered around...

https://twitter.com/IridiumBoss/status/1168582141128650753

And thank you Matt Desch!!

I was about to post that ESA had to make something special about maneuvering around a "Mega-constellation" when adjusting orbits to miss some satellite or the other is pretty routine.

NASA MO.

Do a press release every time you finish a weld on Orion or SLS or move an engine in- or out a teststand. Or move a satellite to prevent it from colliding with another one.

The whole reason this happens with ESA and NASA is because both organizations only exist due to taxpayer's money. Both organizations have an obligation to show their (sometimes involuntary) financial donors what their money is being spent on.

Private companies don't have such obligations. Matt doesn't quite understand that (yet).
Title: Re: Starlink : General Discussion - Thread 2
Post by: dondar on 09/02/2019 08:14 pm
indeed NASA reports everything around SLS.
To complete an analogy it would be noice to show how ESA reports all collision avoidances.
The true is they have reported this "event" because it is the first time they have to deal with SpaceX. They do not report such avoidance maneuvers generally.
What is even more true this tweet "storm" is a typical advertisement program to raise money for  their pet project in UK.
Here is the key pitch:
http://blogs.esa.int/space19plus/programmes/space-debris/

they need a scare crow to get financing.

 ::)
I am afraid they have chosen the wrong target.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Mandella on 09/02/2019 08:15 pm
Going by info in the updates thread it looks like ESA is miffed at SpaceX for "refusing" to move first.

https://forum.nasaspaceflight.com/index.php?topic=48135.msg1987952#msg1987952

No idea who is in the "right" here, if there is even a right of way system worked out yet.

We better get on that. It's only going to get more crowded up there.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Draggendrop on 09/02/2019 09:37 pm
It appears my last post got deleted for triggering someone...

SpaceX has displayed that they are willing to work with most organizations when issues appear.

There is probably  a little more to the story between SpaceX and ESA, particularly when a payload orbital change is presented in this manner..

Title: Re: Starlink : General Discussion - Thread 2
Post by: Lar on 09/02/2019 10:27 pm
It appears my last post got deleted for triggering someone...

SpaceX has displayed that they are willing to work with most organizations when issues appear.

There is probably  a little more to the story between SpaceX and ESA, particularly when a payload orbital change is presented in this manner..

No doubt there is more to the story. At what probability is it reasonable not to perform the maneuver? 1:100,000? (knowing that as the time of the potential interference gets closer the probability will change but it also will take more propellant to successfully avoid...)

If the probability was 1:1,000,000,000 I would not blame SpaceX for "refusing to move first"...
If the probability was 1:10 I would...

Numbers matter.

Also you gotta love @iridiumBoss ... that was world class.
Title: Re: Starlink : General Discussion - Thread 2
Post by: DistantTemple on 09/02/2019 10:35 pm
There are two threads with this same discussion... the other has more

This is cross posting my comment:
AIUI Starlink sats do not have thrusters that can make a significant orbit alteration in a short period. Any collision protection has to be calculated well in advance and takes time. This article confirms that Starlink uses only Hall thrusters: https://spaceflightnow.com/2019/05/15/spacex-releases-new-details-on-starlink-satellite-design/ Hall thrusters deliver perhaps 3 Newtons.

Also perhaps SpaceX were quite confident that a collision was impossible of of vastly lower odds than the ESA calculated.

Therefore we have one reason why it would be slow and not effective for SX to make an orbital change, and another reason why SX was confident there was no need. This puts a different slant on not moveing, from "No, you move", to "there is no need, we are well aware of the situation, and we can only make a minor change at this point, however if you feel strongly you ,ake the change"!

This is a quote and limk to the other thread:
This morning, @ESA's #Aeolus Earth observation satellite fired its thrusters, moving it off a collision course with a
@SpaceX satellite in their #Starlink constellation..

https://twitter.com/esaoperations/status/1168534065118679042
Title: Re: Starlink : General Discussion - Thread 2
Post by: AC in NC on 09/02/2019 11:04 pm
Collision Course?  LOL.  What melodrama.  While I suppose you cannot discount they were actually on a collision course, the infinitely greater liklihood is that ESA Public Affairs just announced to the world they don't even understand the most basic physics of their industry.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Draggendrop on 09/02/2019 11:54 pm
// reference...comment about the existence of the other thread...

Yes and thank you, but I believe most of us are aware of the other thread.

This is the general thread.

 Some of us probably have an opinion and will keep somewhat silent for a stretch,letting others trash around in the other thread for several pages and will see where it leads.

Eventually SpaceX may give their position (pun intended) on the matter....probably when things appear to get a bit overblown.

// edit...having an issue with quotes, probably just me...
Title: Re: Starlink : General Discussion - Thread 2
Post by: Lar on 09/03/2019 12:03 am
Collision Course?  LOL.  What melodrama.  While I suppose you cannot discount they were actually on a collision course, the infinitely greater liklihood is that ESA Public Affairs just announced to the world they don't even understand the most basic physics of their industry.
A chance of a collision isn't the same as a guaranteed collision but prudence suggests diversion. Apparently the ESA standard is 1:10,000 ... is that a commonly accepted standard or just their desire?

Which thread is better for this? This is a general Starlink thread. But the bird involved was launched by the mission in the mission thread. If you want to talk general Starlink, here, I guess. Else there.

If you want to talk about the overall industry approach then consider this one...
https://forum.nasaspaceflight.com/index.php?topic=48954
Title: Re: Starlink : General Discussion - Thread 2
Post by: meekGee on 09/03/2019 02:46 am
Collision Course?  LOL.  What melodrama.  While I suppose you cannot discount they were actually on a collision course, the infinitely greater liklihood is that ESA Public Affairs just announced to the world they don't even understand the most basic physics of their industry.
A chance of a collision isn't the same as a guaranteed collision but prudence suggests diversion. Apparently the ESA standard is 1:10,000 ... is that a commonly accepted standard or just their desire?

Which thread is better for this? This is a general Starlink thread. But the bird involved was launched by the mission in the mission thread. If you want to talk general Starlink, here, I guess. Else there.

If you want to talk about the overall industry approach then consider this one...
https://forum.nasaspaceflight.com/index.php?topic=48954
Something doesn't add up.

If the noninal separation was 10 km (at closest approach) and suppose contact happens at 10 m, if this was straight head-on and if the uncertainties were uniform, the odds would be 1:1,000,000.

But the positional uncertainties are not uniform, they're concentrated on the nominal position, so it's far less probable than even that.

Not being heads-on affects the odds also, but ot just doesn't seem close to 1:1000

This is very sloppy, but it seems orders of magnitudes off.   What's missing?
Title: Re: Starlink : General Discussion - Thread 2
Post by: Draggendrop on 09/03/2019 03:01 am
SpaceNews has posted an article, most of which has been covered in the NSF mission thread.

Of note...

"However, the SOCRATES data predicted a very low probability of collision — less than one in one million — which ordinarily would be far below the threshold for an avoidance maneuver."

from

https://spacenews.com/esa-spacecraft-dodges-potential-collision-with-starlink-satellite/ (https://spacenews.com/esa-spacecraft-dodges-potential-collision-with-starlink-satellite/)

Hopefully we will have more data over the next few days...then get back to business.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Mandella on 09/03/2019 03:11 am
SpaceNews has posted an article, most of which has been covered in the NSF mission thread.

Of note...

"However, the SOCRATES data predicted a very low probability of collision — less than one in one million — which ordinarily would be far below the threshold for an avoidance maneuver."

from

https://spacenews.com/esa-spacecraft-dodges-potential-collision-with-starlink-satellite/ (https://spacenews.com/esa-spacecraft-dodges-potential-collision-with-starlink-satellite/)

Hopefully we will have more data over the next few days...then get back to business.

Seems to be a far better article than the one from CNET that proclaimed that "ESA Narrowly Avoids Starlink Collision" or some such.

In other news, CNET is now banned from my newsfeed (overdue, I know).
Title: Re: Starlink : General Discussion - Thread 2
Post by: mlindner on 09/03/2019 08:47 am
It is absolutely nonsense and unprofessional that ESA would come out and do this. Shame on ESA. They're doing political grandstanding purely to attack. This is not something NASA would ever do. There's no reasonable justification for doing what ESA did.
Title: Re: Starlink : General Discussion - Thread 2
Post by: FutureSpaceTourist on 09/03/2019 10:36 am
Here’s ESA’s latest:

twitter.com/astro_jonny/status/1168825704915656704

Quote
I've got an update from ESA on the 1 in a million vs 1 in 1,000 collision risk analysis for #Starlink 44 and #Aeolus.

ESA says the orbit information they get from USSTRATCOM is ten times better than SOCRATES. Coupled with their own orbital data, they arrived at 1 in 1,000. (1/2)

https://twitter.com/astro_jonny/status/1168825707209928705

Quote
"Operators like ESA and SpaceX can determine the orbit of their own satellites with quite some precision.

"The results we obtained with the more accurate data (1:1000) is therefore much more credible." (2/2)
Title: Re: Starlink : General Discussion - Thread 2
Post by: Maciej Olesinski on 09/03/2019 11:52 am
It is absolutely nonsense and unprofessional that ESA would come out and do this. Shame on ESA. They're doing political grandstanding purely to attack. This is not something NASA would ever do. There's no reasonable justification for doing what ESA did.

I am from Europe and I am ashamed of ESA.

“The greatest enemy is one that has nothing to lose.”
Title: Re: Starlink : General Discussion - Thread 2
Post by: marsbase on 09/03/2019 12:00 pm
Regardless of probabilities, the ESA clearly did not avoid a collision with a "constellation" but rather only one satellite at most.  That shows the political nature of the ESA complaint.  SpaceX has taken the commercial launch market.  Ariane is non-competitive except for government payloads, which don't pay the bills.  Soon the ESA will be using Starlink internet to do their tweeting.  That is the real problem.
Title: Re: Starlink : General Discussion - Thread 2
Post by: su27k on 09/03/2019 12:05 pm
Here’s ESA’s latest:

twitter.com/astro_jonny/status/1168825704915656704

Quote
I've got an update from ESA on the 1 in a million vs 1 in 1,000 collision risk analysis for #Starlink 44 and #Aeolus.

ESA says the orbit information they get from USSTRATCOM is ten times better than SOCRATES. Coupled with their own orbital data, they arrived at 1 in 1,000. (1/2)

Interesting, this seems to imply that the public TLE released by 18SPCS is not the most accurate version, they have a secret dataset more accurate than the public version? Anyone can confirm this?
Title: Re: Starlink : General Discussion - Thread 2
Post by: envy887 on 09/03/2019 01:05 pm
Here’s ESA’s latest:

twitter.com/astro_jonny/status/1168825704915656704

Quote
I've got an update from ESA on the 1 in a million vs 1 in 1,000 collision risk analysis for #Starlink 44 and #Aeolus.

ESA says the orbit information they get from USSTRATCOM is ten times better than SOCRATES. Coupled with their own orbital data, they arrived at 1 in 1,000. (1/2)

Interesting, this seems to imply that the public TLE released by 18SPCS is not the most accurate version, they have a secret dataset more accurate than the public version? Anyone can confirm this?

Probably not secret so much as not updated as often. This has come up before in regards to Starlink:

TS Kelso (of CelesTrak) has some concerns about the tracking of the constellation:

https://twitter.com/TSKelso/status/1141906661499711491

Hi SWGlassPit, Can you possibly explain this for me?

I would not put too much into this tweet.

18 SPCS is tasked with monitoring and avoidance, among many other duties.

This briefing, pdf will give insight...
https://advancedssa.com/assets/img/workshop/presentations/JSpOC-18SPCS_CONOPS.pdf (https://advancedssa.com/assets/img/workshop/presentations/JSpOC-18SPCS_CONOPS.pdf)

18 SPCS has many resources available  to them and are in possession of more detailed data than just TLE's.

If there is an issue, they are able to communicate directly with the payload owner..
https://www.af.mil/News/Article-Display/Article/1335482/18th-space-control-squadron-keeping-watch-up-above/ (https://www.af.mil/News/Article-Display/Article/1335482/18th-space-control-squadron-keeping-watch-up-above/)

The 18th Space Control Squadron maintains the space catalog.
https://www.afspc.af.mil/News/Article-Display/Article/1459151/18th-spcs-stands-guard-over-space/ (https://www.afspc.af.mil/News/Article-Display/Article/1459151/18th-spcs-stands-guard-over-space/)

The latest info is not neccessarily in the catalog.

I am sure 18 SPCS and SpaceX are more than aware of the entire situation.

The men and women of 18SPCS do an outstanding job, a thankless job at times. One must be careful to not "cry wolf" too often...

just my 2 cents.
Title: Re: Starlink : General Discussion - Thread 2
Post by: envy887 on 09/03/2019 01:09 pm
Collision Course?  LOL.  What melodrama.  While I suppose you cannot discount they were actually on a collision course, the infinitely greater liklihood is that ESA Public Affairs just announced to the world they don't even understand the most basic physics of their industry.
A chance of a collision isn't the same as a guaranteed collision but prudence suggests diversion. Apparently the ESA standard is 1:10,000 ... is that a commonly accepted standard or just their desire?

Which thread is better for this? This is a general Starlink thread. But the bird involved was launched by the mission in the mission thread. If you want to talk general Starlink, here, I guess. Else there.

If you want to talk about the overall industry approach then consider this one...
https://forum.nasaspaceflight.com/index.php?topic=48954
Something doesn't add up.

If the noninal separation was 10 km (at closest approach) and suppose contact happens at 10 m, if this was straight head-on and if the uncertainties were uniform, the odds would be 1:1,000,000.

But the positional uncertainties are not uniform, they're concentrated on the nominal position, so it's far less probable than even that.

Not being heads-on affects the odds also, but ot just doesn't seem close to 1:1000

This is very sloppy, but it seems orders of magnitudes off.   What's missing?

Per the SpaceNews article, the SOCRATES data predicted a 4 km miss but ESA had data (both internal and from USSTRATCOM) that indicated a much closer pass.

https://spacenews.com/esa-spacecraft-dodges-potential-collision-with-starlink-satellite/
Title: Re: Starlink : General Discussion - Thread 2
Post by: Lar on 09/03/2019 01:41 pm
This is not something NASA would ever do. 
Citation needed. There certainly are elements within NASA (remember, not monolithic, nor is ESA) that have grandstanded about various things in the past.  Let's not politicise this any more than necessary.
Title: Re: Starlink : General Discussion - Thread 2
Post by: su27k on 09/03/2019 01:51 pm
Here’s ESA’s latest:

twitter.com/astro_jonny/status/1168825704915656704

Quote
I've got an update from ESA on the 1 in a million vs 1 in 1,000 collision risk analysis for #Starlink 44 and #Aeolus.

ESA says the orbit information they get from USSTRATCOM is ten times better than SOCRATES. Coupled with their own orbital data, they arrived at 1 in 1,000. (1/2)

Interesting, this seems to imply that the public TLE released by 18SPCS is not the most accurate version, they have a secret dataset more accurate than the public version? Anyone can confirm this?

Probably not secret so much as not updated as often. This has come up before in regards to Starlink:

Yeah, but previous discussion never reached a conclusion as to whether 18SPCS is holding back more up to date dataset. And the TLE age issue has been resolved since then, if you check Starlink and Aeolus' TLE age on http://celestrak.com, they are both less than one day old, so very much up to date.

The SpaceNews article (https://spacenews.com/esa-spacecraft-dodges-potential-collision-with-starlink-satellite/) was updated to say ESA received notification 5 days before the close approach, presumably SpaceNews run SOCRATES after the ESA tweet which is yesterday, so the data used by SpaceNews' SOCRATES run should be only 2 days before the close approach at maximal, which is 3 days after the 5 days notification.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 09/03/2019 02:01 pm
The SpaceNews article (https://spacenews.com/esa-spacecraft-dodges-potential-collision-with-starlink-satellite/) was updated to say ESA received notification 5 days before the close approach, presumably SpaceNews run SOCRATES after the ESA tweet which is yesterday, so the data used by SpaceNews' SOCRATES run should be only 2 days before the close approach at maximal, which is 3 days after the 5 days notification.

Did you really read that article?  Maybe you should read it again.  It doesn't say anything about Space News running SOCRATES.  It does say that ESA monitored the situation from the time they were informed of it and then made the decision to adjust the orbit the day before the potential conjuction.  The idea that Space News somehow ran a better analysis of the situation than ESA is ridiculous.
Title: Re: Starlink : General Discussion - Thread 2
Post by: meekGee on 09/03/2019 02:06 pm
Well, even if the best data ESA had exceeded their threshold for avoidance, why didn't they just...  avoid?
Title: Re: Starlink : General Discussion - Thread 2
Post by: su27k on 09/03/2019 02:10 pm
The SpaceNews article (https://spacenews.com/esa-spacecraft-dodges-potential-collision-with-starlink-satellite/) was updated to say ESA received notification 5 days before the close approach, presumably SpaceNews run SOCRATES after the ESA tweet which is yesterday, so the data used by SpaceNews' SOCRATES run should be only 2 days before the close approach at maximal, which is 3 days after the 5 days notification.

Did you really read that article?  Maybe you should read it again.  It doesn't say anything about Space News running SOCRATES.  It does say that ESA monitored the situation from the time they were informed of it and then made the decision to adjust the orbit the day before the potential conjuction.  The idea that Space News somehow ran a better analysis of the situation than ESA is ridiculous.

Of course I read it, twice, once before they did the update, once after they did the update. If SpaceNews didn't run SOCRATES, where did this comes from?

Quote
According to a list of conjunctions called the Satellite Orbital Conjunction Reports Assessing Threatening Encounters in Space (SOCRATES), maintained by the Center for Space Standards & Innovation, Aeolus was predicted to have a close approach shortly after 7 a.m. Eastern Sept. 2 with a satellite identified as “Starlink AV” for its international designation, 2019-029AV. The two satellites were predicted to come within about four kilometers of each other, at a relative velocity of 14.4 kilometers per second. However, the SOCRATES data predicted a very low probability of collision — less than one in one million — which ordinarily would be far below the threshold for an avoidance maneuver.

And where did I suggest SpaceNews' analysis is better? What I'd like to know is the cause of the different results, is it because 18SPCS public TLE data is not accurate? Or something else.

And if public TLE data is not accurate, is it because 18SPCS is holding back more accurate dataset, or is it because ESA is not sharing up to date orbital data with 18SPCS? Both are concerning, especially given a few pages back some people are concerned the public TLE age is too old, but if 18SPCS has a secret dataset which it only shares with operators, then the age of the public TLE doesn't matter. It's all tied together, you can't argue both ways.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Robotbeat on 09/03/2019 02:15 pm
Well, even if the best data ESA had exceeded their threshold for avoidance, why didn't they just...  avoid?
That's exactly what they did.
Title: Re: Starlink : General Discussion - Thread 2
Post by: cebri on 09/03/2019 02:18 pm
I think SpaceX will not make any further comments, as I don't believe they want a public fight with an international agency and keep this event more time in the news.

However, if the current databases are not accurate enough to eliminate the uncertainty of a collision, I do wonder what advancements can be made in that camp. Maybe sat constellations operators should be forced to share in real time the position of each of their satelites, including altitude, trayectory and velocity.

Well, even if the best data ESA had exceeded their threshold for avoidance, why didn't they just...  avoid?
That's exactly what they did.

I think he means why didn't just avoid and shut up about it. Until we know what spacex told them, it is very hard to know what went on.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Robotbeat on 09/03/2019 02:22 pm
The SpaceNews article (https://spacenews.com/esa-spacecraft-dodges-potential-collision-with-starlink-satellite/) was updated to say ESA received notification 5 days before the close approach, presumably SpaceNews run SOCRATES after the ESA tweet which is yesterday, so the data used by SpaceNews' SOCRATES run should be only 2 days before the close approach at maximal, which is 3 days after the 5 days notification.

Did you really read that article?  Maybe you should read it again.  It doesn't say anything about Space News running SOCRATES.  It does say that ESA monitored the situation from the time they were informed of it and then made the decision to adjust the orbit the day before the potential conjuction.  The idea that Space News somehow ran a better analysis of the situation than ESA is ridiculous.

Of course I read it, twice, once before they did the update, once after they did the update. If SpaceNews didn't run SOCRATES, where did this comes from?

Quote
According to a list of conjunctions called the Satellite Orbital Conjunction Reports Assessing Threatening Encounters in Space (SOCRATES), maintained by the Center for Space Standards & Innovation, Aeolus was predicted to have a close approach shortly after 7 a.m. Eastern Sept. 2 with a satellite identified as “Starlink AV” for its international designation, 2019-029AV. The two satellites were predicted to come within about four kilometers of each other, at a relative velocity of 14.4 kilometers per second. However, the SOCRATES data predicted a very low probability of collision — less than one in one million — which ordinarily would be far below the threshold for an avoidance maneuver.

And where did I suggest SpaceNews' analysis is better? What I'd like to know is the cause of the different results, is it because 18SPCS public TLE data is not accurate? Or something else.

And if public TLE data is not accurate, is it because 18SPCS is holding back more accurate dataset, or is it because ESA is not sharing up to date orbital data with 18SPCS? Both are concerning, especially given a few pages back some people are concerned the public TLE age is too old, but if 18SPCS has a secret dataset which it only shares with operators, then the age of the public TLE doesn't matter. It's all tied together, you can't argue both ways.
Indeed. ESA apparently isn't making their best data public in real-time.

Actually, I think all operators should have to share their best position data in real-time. With regulators. And there should be actual regulations regarding how this is all de-conflicted. ESA (who is an investor in OneWeb and whose ArianeSpace is providing many satellites and launches for) making a public relations ploy (even though their own best data about satellite position is not public!) about this is not super helpful. OneWeb using concern-trolling ("Responsible Space") as a marketing platform is also not helpful. There needs to be a public database of this stuff to the highest possible precision available in real-time, and it needs to be deconflicted using an ATC-like entity.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Tywin on 09/03/2019 02:47 pm
The SpaceNews article (https://spacenews.com/esa-spacecraft-dodges-potential-collision-with-starlink-satellite/) was updated to say ESA received notification 5 days before the close approach, presumably SpaceNews run SOCRATES after the ESA tweet which is yesterday, so the data used by SpaceNews' SOCRATES run should be only 2 days before the close approach at maximal, which is 3 days after the 5 days notification.

Did you really read that article?  Maybe you should read it again.  It doesn't say anything about Space News running SOCRATES.  It does say that ESA monitored the situation from the time they were informed of it and then made the decision to adjust the orbit the day before the potential conjuction.  The idea that Space News somehow ran a better analysis of the situation than ESA is ridiculous.

Of course I read it, twice, once before they did the update, once after they did the update. If SpaceNews didn't run SOCRATES, where did this comes from?

Quote
According to a list of conjunctions called the Satellite Orbital Conjunction Reports Assessing Threatening Encounters in Space (SOCRATES), maintained by the Center for Space Standards & Innovation, Aeolus was predicted to have a close approach shortly after 7 a.m. Eastern Sept. 2 with a satellite identified as “Starlink AV” for its international designation, 2019-029AV. The two satellites were predicted to come within about four kilometers of each other, at a relative velocity of 14.4 kilometers per second. However, the SOCRATES data predicted a very low probability of collision — less than one in one million — which ordinarily would be far below the threshold for an avoidance maneuver.

And where did I suggest SpaceNews' analysis is better? What I'd like to know is the cause of the different results, is it because 18SPCS public TLE data is not accurate? Or something else.

And if public TLE data is not accurate, is it because 18SPCS is holding back more accurate dataset, or is it because ESA is not sharing up to date orbital data with 18SPCS? Both are concerning, especially given a few pages back some people are concerned the public TLE age is too old, but if 18SPCS has a secret dataset which it only shares with operators, then the age of the public TLE doesn't matter. It's all tied together, you can't argue both ways.
Indeed. ESA apparently isn't making their best data public in real-time.

Actually, I think all operators should have to share their best position data in real-time. With regulators. And there should be actual regulations regarding how this is all de-conflicted. ESA (who is an investor in OneWeb and whose ArianeSpace is providing many satellites and launches for) making a public relations ploy (even though their own best data about satellite position is not public!) about this is not super helpful. OneWeb using concern-trolling ("Responsible Space") as a marketing platform is also not helpful. There needs to be a public database of this stuff to the highest possible precision available in real-time, and it needs to be deconflicted using an ATC-like entity.

Who is ATC?

By the way for general regulations and future resolutions, we have this thread  :)

https://forum.nasaspaceflight.com/index.php?topic=48954.msg1988270#new

Title: Re: Starlink : General Discussion - Thread 2
Post by: mn on 09/03/2019 03:00 pm

...

Who is ATC?
...


That would most likely be Air Traffic Control
Title: Re: Starlink : General Discussion - Thread 2
Post by: SWGlassPit on 09/03/2019 03:04 pm

...

Who is ATC?
...


That would most likely be Air Traffic Control

I think the question was more to the point of, "who would be given the authority to act as ATC?"
Title: Re: Starlink : General Discussion - Thread 2
Post by: meekGee on 09/03/2019 03:18 pm
Well, even if the best data ESA had exceeded their threshold for avoidance, why didn't they just...  avoid?
That's exactly what they did.
Well first they demanded that SpaceX move,  then insinuated that somehow SpaceX should have moved but refused.

Somewhere in the middle, they moved as they should have.

Not the same.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Alastor on 09/03/2019 03:24 pm
Actually, I think all operators should have to share their best position data in real-time. With regulators. And there should be actual regulations regarding how this is all de-conflicted. ESA (who is an investor in OneWeb and whose ArianeSpace is providing many satellites and launches for) making a public relations ploy (even though their own best data about satellite position is not public!) about this is not super helpful. OneWeb using concern-trolling ("Responsible Space") as a marketing platform is also not helpful. There needs to be a public database of this stuff to the highest possible precision available in real-time, and it needs to be deconflicted using an ATC-like entity.

If you read Forbe's interview of an ESA person (https://www.forbes.com/sites/jonathanocallaghan/2019/09/02/spacex-refused-to-move-a-starlink-satellite-at-risk-of-collision-with-a-european-satellite/#2d00de0d1f62 (https://www.forbes.com/sites/jonathanocallaghan/2019/09/02/spacex-refused-to-move-a-starlink-satellite-at-risk-of-collision-with-a-european-satellite/#2d00de0d1f62)), that's actually the whole point they are trying to make.

They didn't say SpaceX was wrong (they actually said nobody was wrong).
They didn't say SpaceX should have moved (even though they asked them to do so).
They however say that it's an issue that there is no regulator nor regulation to handle this kind of situation that they envision becoming extremely frequent in the future.

And frankly, I think they are right about this. The different actors need to establish if not an international authority, at least international rules on the topic of collision avoidance : Who should avoid ? Based on what safety criterium ? Based on whose data ? And what maneuver should be done ?

An interesting point I have seen raised, that's of particular concern if we are talking about automatic avoidance systems is what happens if both satellite decide they should avoid and decide to do so in a way that keeps them on a collision course ? Does that mean that both satellites need to communicate to do such things ? If so, then it means we need communications standards for this as well and that we need to decide what happens if there is a conjunction between a satellite that's automatically avoiding and one that's exclusively ground controlled.

Basically, the point the ESA is making is that we need to have a system similar to ATC, but with an additional complexity factor which is that orbital mechanics forbid having a national authority for that. And we should probably do that before there is a colision caused by this lack of regulations.

They should have been clearer about their point from the get go, though.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Alastor on 09/03/2019 03:32 pm
Well, even if the best data ESA had exceeded their threshold for avoidance, why didn't they just...  avoid?
That's exactly what they did.
Well first they demanded that SpaceX move,  then insinuated that somehow SpaceX should have moved but refused.

Somewhere in the middle, they moved as they should have.

Not the same.

Shouldn't SpaceX have moved though ?
I read somewhere that they were on this orbit before Starlink even launched. So clearly SpaceX's satellite is the one that came on a collision course.
Why should ESA's satellite be the one moving ?

Also ESA's satellite is a very expensive satellite whose life span is reduced by this kind of maneuvers. SpaceX's satellite is a cheap one which is performing experiments about deorbiting, so it doesn't care so much about conserving propellant.

So again, why should ESA's satellite be the one performing the maneuver ?

Another point that's concerning to me is : If it had been the NASA asking SpaceX to move their satellite, would their reaction have been the same ? I personally don't think so.
Title: Re: Starlink : General Discussion - Thread 2
Post by: meekGee on 09/03/2019 03:35 pm
Well, even if the best data ESA had exceeded their threshold for avoidance, why didn't they just...  avoid?
That's exactly what they did.
Well first they demanded that SpaceX move,  then insinuated that somehow SpaceX should have moved but refused.

Somewhere in the middle, they moved as they should have.

Not the same.

Shouldn't SpaceX have moved though ?
I read somewhere that they were on this orbit before Starlink even launched. So clearly SpaceX's satellite is the one that came on a collision course.
Why should ESA's satellite be the one moving ?

Also ESA's satellite is a very expensive satellite whose life span is reduced by this kind of maneuvers. SpaceX's satellite is a cheap one which is performing experiments about deorbiting, so it doesn't care so much about conserving propellant.

So again, why should ESA's satellite be the one performing the maneuver ?

Another point that's concerning to me is : If it had been the NASA asking SpaceX to move their satellite, would their reaction have been the same ? I personally don't think so.
There's no such rule.  Where did this information come from?
Title: Re: Starlink : General Discussion - Thread 2
Post by: su27k on 09/03/2019 03:40 pm
If you read Forbe's interview of an ESA person (https://www.forbes.com/sites/jonathanocallaghan/2019/09/02/spacex-refused-to-move-a-starlink-satellite-at-risk-of-collision-with-a-european-satellite/#2d00de0d1f62 (https://www.forbes.com/sites/jonathanocallaghan/2019/09/02/spacex-refused-to-move-a-starlink-satellite-at-risk-of-collision-with-a-european-satellite/#2d00de0d1f62)), that's actually the whole point they are trying to make.

They didn't say SpaceX was wrong (they actually said nobody was wrong).
They didn't say SpaceX should have moved (even though they asked them to do so).

That may be what the forbes article wants you to believe by using words like "refused"/"declined" - which BTW the SpaceNews article didn't use - but if you read the article (and the SpaceNews article) carefully, there's no indication at all that ESA has asked SpaceX to move Starlink. All it says is:
Quote
“Based on this we informed SpaceX, who replied and said that they do not plan to take action,” says Krag, who said SpaceX informed them via email

SpaceNews has similar wording
Quote
“We have informed SpaceX and they acknowledged,” he said. “Over the days the collision probability exceeded the decision threshold and we started the maneuver preparation and shared our plans with SpaceX. The decision to maneuver was then made the day before.”

No where in the article said SpaceX was asked to move.

Edit: And the author of the forbes article just clarified this:

https://twitter.com/Astro_Jonny/status/1168859502067834881

Quote
Just to quickly clarify again
@FastCompany
 et al, ESA did NOT ask SpaceX to move. SpaceX simply said they would not move their #Starlink satellite, necessitating an evasive manoeuvre from #Aeolus.
Title: Re: Starlink : General Discussion - Thread 2
Post by: meekGee on 09/03/2019 03:53 pm
Well, even if the best data ESA had exceeded their threshold for avoidance, why didn't they just...  avoid?
That's exactly what they did.
Well first they demanded that SpaceX move,  then insinuated that somehow SpaceX should have moved but refused.

Somewhere in the middle, they moved as they should have.

Not the same.

Shouldn't SpaceX have moved though ?
I read somewhere that they were on this orbit before Starlink even launched. So clearly SpaceX's satellite is the one that came on a collision course.
Why should ESA's satellite be the one moving ?

Also ESA's satellite is a very expensive satellite whose life span is reduced by this kind of maneuvers. SpaceX's satellite is a cheap one which is performing experiments about deorbiting, so it doesn't care so much about conserving propellant.

So again, why should ESA's satellite be the one performing the maneuver ?

Another point that's concerning to me is : If it had been the NASA asking SpaceX to move their satellite, would their reaction have been the same ? I personally don't think so.
About the second argument, it makes no sense.  BMWs don't get right away over Fiats.

As for the Euro angle, ESA virtually guaranteed making this a political issue. What they should have done was quietly try to establish some regulations on this matter, not start a PR war.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Tywin on 09/03/2019 03:57 pm
Well, even if the best data ESA had exceeded their threshold for avoidance, why didn't they just...  avoid?
That's exactly what they did.
Well first they demanded that SpaceX move,  then insinuated that somehow SpaceX should have moved but refused.

Somewhere in the middle, they moved as they should have.

Not the same.

Shouldn't SpaceX have moved though ?
I read somewhere that they were on this orbit before Starlink even launched. So clearly SpaceX's satellite is the one that came on a collision course.
Why should ESA's satellite be the one moving ?

Also ESA's satellite is a very expensive satellite whose life span is reduced by this kind of maneuvers. SpaceX's satellite is a cheap one which is performing experiments about deorbiting, so it doesn't care so much about conserving propellant.

So again, why should ESA's satellite be the one performing the maneuver ?

Another point that's concerning to me is : If it had been the NASA asking SpaceX to move their satellite, would their reaction have been the same ? I personally don't think so.
There's no such rule.  Where did this information come from?

That rule is logical rule...even in automovil transport when you are in a bridge of only one way, and you with a motorcycle want to pass and a truck too...well normally the bigger vehicles have priority...

But anyway that is because is so important regulate all this...
Title: Re: Starlink : General Discussion - Thread 2
Post by: Alastor on 09/03/2019 04:06 pm
There's no such rule.  Where did this information come from?

Did you even read me ?
I even specifically said there was no regulation on this in my previous post.
All I'm saying is you are making a fuss as if ESA was necessarily the ones who should move since they were worried about a collision. It's not that clear that they should be the ones to do so.

About the second argument, it makes no sense.  BMWs don't get right away over Fiats.

As for the Euro angle, ESA virtually guaranteed making this a political issue. What they should have done was quietly try to establish some regulations on this matter, not start a PR war.

BMW's don't cost 300M$.
Cars can make a stop at a fuel station if they run out of fuel and don't have to be thrown away.
Your comparison absolutely does not hold. It's these specificities that make this argument hold.

What I'm reading from the info I have seen is that they made this a public and political issue precisely because when they first tried to start a dialogue about that kind of things with SpaceX, they simply got ignored.
It's not ideal, but maybe they felt they didn't really have a choice if they wanted the issue to be addressed.

Also you are way overreacting. It's not a war if we don't make it a war.

No where in the article said SpaceX was asked to move.
Edit: And the author of the forbes article just clarified this

Good point.
Though they clearly implied that they think SpaceX should have been the ones to move. Or at least the article implied that.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 09/03/2019 04:16 pm
https://twitter.com/jeff_foust/status/1168919094265044996
Quote
SpaceX, in a new statement, says they were aware of the potential Aeolus/Starlink collision, but at first the probability was low. When the probability increased, “a bug in our on-call paging system prevented the Starlink operator from seeing the follow on correspondence.”

https://twitter.com/jeff_foust/status/1168919423195013120
Quote
SpaceX said had they been aware of the increased probability risk, “we would have coordinated with ESA to determine best approach with their continuing with their maneuver or our performing a maneuver.”]SpaceX said had they been aware of the increased probability risk, “we would have coordinated with ESA to determine best approach with their continuing with their maneuver or our performing a maneuver.”

Can we stop with the "evil ESA was overstating the risk" crap now?
Title: Re: Starlink : General Discussion - Thread 2
Post by: Lar on 09/03/2019 04:22 pm
Text of the statement courtesy of Loren Grush


https://twitter.com/lorengrush/status/1168917747109191681
Title: Re: Starlink : General Discussion - Thread 2
Post by: speedevil on 09/03/2019 04:24 pm
I note wikipedias page on the satellite in question https://en.wikipedia.org/wiki/ADM-Aeolus#cite_note-%E2%80%9D2019-06-27_Spectrum%E2%80%9D-13 states that it is already doing weekly manoevers to maintain orbit.
It would be interesting to know the magnitude of the previous burns, and this one.
Also if SpaceX bird has manoevered recently - if not - burning to a conjunction in the weeks prior pretty much puts the fault on one side.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Lar on 09/03/2019 04:24 pm
Seems clear to me that some overall coordination is needed. What is not clear is that it has to be done via "regulation" (what international body has regulatory authority??).

Take further discussion of that idea here I think

https://forum.nasaspaceflight.com/index.php?topic=48954
Title: Re: Starlink : General Discussion - Thread 2
Post by: Marci on 09/03/2019 04:26 pm
So the main problem I see is a lot of miscommunication and a lack of cooperation between SpaceX and ESA.

If SpaceX wants Starlink to be successfull they should really start to consider the concerns of the other players. There will be new rules in the future, just because the amount of new satellites is too big. And if you want these regulations be in favour of your plans, you need the others to trust you.

So it should be in SpaceX own interest to have a better relation with ESA (and the scientific community in general) in the future.
Title: Re: Starlink : General Discussion - Thread 2
Post by: envy887 on 09/03/2019 04:30 pm
So the main problem I see is a lot of miscommunication and a lack of cooperation between SpaceX and ESA.

If SpaceX wants Starlink to be successfull they should really start to consider the concerns of the other players. There will be new rules in the future, just because the amount of new satellites is too big. And if you want these regulations be in favour of your plans, you need the others to trust you.

So it should be in SpaceX own interest to have a better relation with ESA (and the scientific community in general) in the future.

I'll note that according to both ESA and reporters in direct contact with ESA sources, ESA never ASKED SpaceX to move. ESA simply "informed" SpaceX of ESA's calculated collision risk (which incorporated ESA internal positioning data not available to SpaceX), and SpaceX "who replied and said that they do not plan to take action”.

ESA might simply have been asking "our data shows a 1:1000 risk, are you planning to maneuver?", to which SpaceX replied "No". This was all the information ESA needed to make the decision to execute their own maneuver which they did.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Lar on 09/03/2019 04:40 pm
So the main problem I see is a lot of miscommunication and a lack of cooperation between SpaceX and ESA.

If SpaceX wants Starlink to be successfull they should really start to consider the concerns of the other players. There will be new rules in the future, just because the amount of new satellites is too big. And if you want these regulations be in favour of your plans, you need the others to trust you.

So it should be in SpaceX own interest to have a better relation with ESA (and the scientific community in general) in the future.
This is not the spin I'd give this. There seems to be a conflict between ESA saying "SpaceX never communicates with us" and SpaceX saying "we exchanged emails about this and jointly decided no action was warranted, and we're sorry we botched comms when there was an update to the probability"  (both paraphrases)

There may be elements in ESA that would like to make SpaceX look bad, since there is some connection between ESA-ArianeSpace-OneWeb (a direct competitor to Starlink)

Let's not ourselves also play that game ok?
Title: Re: Starlink : General Discussion - Thread 2
Post by: Draggendrop on 09/03/2019 04:42 pm
So the main problem I see is a lot of miscommunication and a lack of cooperation between SpaceX and ESA.

If SpaceX wants Starlink to be successfull they should really start to consider the concerns of the other players. There will be new rules in the future, just because the amount of new satellites is too big. And if you want these regulations be in favour of your plans, you need the others to trust you.

So it should be in SpaceX own interest to have a better relation with ESA (and the scientific community in general) in the future.

In this instance I believe ESA could have handled this in a more professional manner.  Twitter is not the venue to use for a general avoidance maneuver or to use this situation for other means without direct dialogue with those in a conflicting situation.

oops...been ninja'd
Title: Re: Starlink : General Discussion - Thread 2
Post by: guckyfan on 09/03/2019 04:44 pm
Seems there are contradicting statements. This ESA statement sounds more positive on SpaceX than the SpaceX statement.

An ESA comment on n-tv a german news channel.

https://www.n-tv.de/wissen/Esa-Satellit-umfliegt-SpaceX-Satelliten-article21248848.html

Quote
Zuvor hatte die ESA SpaceX kontaktiert. Zusammen wurde entschieden, dass "Aeolus" ausweicht. Die Absprache sei wichtig, sagte Holger Krag, der Leiter des Esa-Büros für Raumfahrtrückstände. Ansonsten könnte es im schlimmsten Fall sein, dass beide Satelliten in die gleiche Richtung ausweichen und so weiter aufeinanderzusteuern. Die Absprache mit SpaceX funktionierte laut dem Experten gut. Das sei nicht immer so: "Es gibt Satellitenbetreiber, die reagieren gar nicht, wenn man sie anschreibt."

Before (ESA did the course correction) ESA had contacted SpaceX. Together they decided that "Aeolus" makes the avoidance maneuver. Agreement is important, said Holger Krag, head of ESA office for Space flight (not sure how to translate Rückstande - which means remnants). Otherwise worst case both satellites maneuver in the same direction and stay on collision course. Communication with SpaceX worked well according to the expert. That's not always the case. "There are satellite operators that don't react at all if contacted."
Title: Re: Starlink : General Discussion - Thread 2
Post by: envy887 on 09/03/2019 04:45 pm
So the main problem I see is a lot of miscommunication and a lack of cooperation between SpaceX and ESA.

If SpaceX wants Starlink to be successfull they should really start to consider the concerns of the other players. There will be new rules in the future, just because the amount of new satellites is too big. And if you want these regulations be in favour of your plans, you need the others to trust you.

So it should be in SpaceX own interest to have a better relation with ESA (and the scientific community in general) in the future.

In this instance I believe ESA could have handled this in a more professional manner.  Twitter is not the venue to use for a general avoidance maneuver or to use this situation for other means without direct dialogue with those in a conflicting situation.

oops...been ninja'd
ESA went to twitter long after the maneuver had been performed. And they did have a direct dialog with SpaceX, per their statements to Forbes and SpaceNews.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Draggendrop on 09/03/2019 04:57 pm
The SpaceNews article (https://spacenews.com/esa-spacecraft-dodges-potential-collision-with-starlink-satellite/) was updated to say ESA received notification 5 days before the close approach, presumably SpaceNews run SOCRATES after the ESA tweet which is yesterday, so the data used by SpaceNews' SOCRATES run should be only 2 days before the close approach at maximal, which is 3 days after the 5 days notification.

Did you really read that article?  Maybe you should read it again.  It doesn't say anything about Space News running SOCRATES.  It does say that ESA monitored the situation from the time they were informed of it and then made the decision to adjust the orbit the day before the potential conjuction.  The idea that Space News somehow ran a better analysis of the situation than ESA is ridiculous.

Of course I read it, twice, once before they did the update, once after they did the update. If SpaceNews didn't run SOCRATES, where did this comes from?

Quote
According to a list of conjunctions called the Satellite Orbital Conjunction Reports Assessing Threatening Encounters in Space (SOCRATES), maintained by the Center for Space Standards & Innovation, Aeolus was predicted to have a close approach shortly after 7 a.m. Eastern Sept. 2 with a satellite identified as “Starlink AV” for its international designation, 2019-029AV. The two satellites were predicted to come within about four kilometers of each other, at a relative velocity of 14.4 kilometers per second. However, the SOCRATES data predicted a very low probability of collision — less than one in one million — which ordinarily would be far below the threshold for an avoidance maneuver.

And where did I suggest SpaceNews' analysis is better? What I'd like to know is the cause of the different results, is it because 18SPCS public TLE data is not accurate? Or something else.

And if public TLE data is not accurate, is it because 18SPCS is holding back more accurate dataset, or is it because ESA is not sharing up to date orbital data with 18SPCS? Both are concerning, especially given a few pages back some people are concerned the public TLE age is too old, but if 18SPCS has a secret dataset which it only shares with operators, then the age of the public TLE doesn't matter. It's all tied together, you can't argue both ways.

The TLE data set issued is for general consumption. The accuracy is reasonable and it is up to the end user how to present, modify or tease accuracy from various elements.

There is no "more accurate" TLE set for general consumption.

Several billions of dollars of equipment are in use and/or available for general tracking and for refined operations.

Radar, laser and GPS equipment, to name a few, have levels of accuracy and abilities to modify beam patterns and apply mathematical modifications to extract increased accuracy.

There is no way that this increased accuracy will be let out in the wild...for obvious reasons.

Entities can engage in agreements for increased accuracy pertaining to their payloads. This data can again be modified as the user deems to their desired standard.

There is no universal standard that everyone uses to tease data...but the methods can be verified mathematically.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Draggendrop on 09/03/2019 05:05 pm
So the main problem I see is a lot of miscommunication and a lack of cooperation between SpaceX and ESA.

If SpaceX wants Starlink to be successfull they should really start to consider the concerns of the other players. There will be new rules in the future, just because the amount of new satellites is too big. And if you want these regulations be in favour of your plans, you need the others to trust you.

So it should be in SpaceX own interest to have a better relation with ESA (and the scientific community in general) in the future.

In this instance I believe ESA could have handled this in a more professional manner.  Twitter is not the venue to use for a general avoidance maneuver or to use this situation for other means without direct dialogue with those in a conflicting situation.

oops...been ninja'd
ESA went to twitter long after the maneuver had been performed. And they did have a direct dialog with SpaceX, per their statements to Forbes and SpaceNews.

True but a certain twitter handle was stating inside information from someone in ESA , probably not sanctioned, that started and continued this mess. I followed this "drama" during the early part...not pretty. Some of it ended in a Forbes article and not as it is presented now.

It appears to be handled now and hopefully kept off twitter in the future.
Title: Re: Starlink : General Discussion - Thread 2
Post by: aameise9 on 09/03/2019 06:54 pm
Interview on "space safety" with ESA expert Holger Krag was just published by German quality daily (Frankfurter Allgemeine Zeitung):

https://www.faz.net/aktuell/wissen/weltraum/esa-satellit-muss-musks-starlink-satellit-ausweichen-16366503.html (https://www.faz.net/aktuell/wissen/weltraum/esa-satellit-muss-musks-starlink-satellit-ausweichen-16366503.html)

IMHO, his statements are balanced and reasonable.  No bashing that I can perceive.  He argues that new procedures -- largely automated and autonomous -- need to be discussed and agreed upon, because such incidents are bound to become increasingly frequent.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Lar on 09/03/2019 07:22 pm
Interview on "space safety" with ESA expert Holger Krag was just published by German quality daily (Frankfurter Allgemeine Zeitung):

https://www.faz.net/aktuell/wissen/weltraum/esa-satellit-muss-musks-starlink-satellit-ausweichen-16366503.html (https://www.faz.net/aktuell/wissen/weltraum/esa-satellit-muss-musks-starlink-satellit-ausweichen-16366503.html)

IMHO, his statements are balanced and reasonable.  No bashing that I can perceive.  He argues that new procedures -- largely automated and autonomous -- need to be discussed and agreed upon, because such incidents are bound to become increasingly frequent.
Did he discuss that ESA is seeking funding for just such a system?
Title: Re: Starlink : General Discussion - Thread 2
Post by: alexterrell on 09/03/2019 07:39 pm
So the main problem I see is a lot of miscommunication and a lack of cooperation between SpaceX and ESA.

If SpaceX wants Starlink to be successfull they should really start to consider the concerns of the other players. There will be new rules in the future, just because the amount of new satellites is too big. And if you want these regulations be in favour of your plans, you need the others to trust you.

So it should be in SpaceX own interest to have a better relation with ESA (and the scientific community in general) in the future.

In this instance I believe ESA could have handled this in a more professional manner.  Twitter is not the venue to use for a general avoidance maneuver or to use this situation for other means without direct dialogue with those in a conflicting situation.

oops...been ninja'd
Twitter was used to report the news after the event.

SpaceX have admitted that they were partly at fault:
Quote
A SpaceX spokesperson said a bug in its on-call operating system prevented the team from seeing that the risk of a collision with the ESA craft may have increased.

“Had the Starlink operator seen the correspondence, we would have coordinated with ESA to determine best approach with their continuing with their manoeuvre or our performing a manoeuvre,” the spokesperson said.

This is a bit like pulling out of a junction without seeing another car, with both having equal priority, but the other driver has plenty of time to avoid you, and does so. A quick "sorry" is the end of the problem.

Except in this case .... some sort of procedures will be needed to support 10s of thousands of satellites in orbit. For everyone's sake. 

By the way, who is responsible for warning SpaceX about collision threats? Is this the USAF? Do they provide this as a service to all satellite operators?
Title: Re: Starlink : General Discussion - Thread 2
Post by: envy887 on 09/03/2019 07:44 pm
By the way, who is responsible for warning SpaceX about collision threats? Is this the USAF? Do they provide this as a service to all satellite operators?

Yes and yes.
Title: Re: Starlink : General Discussion - Thread 2
Post by: alexterrell on 09/03/2019 07:44 pm
Interview on "space safety" with ESA expert Holger Krag was just published by German quality daily (Frankfurter Allgemeine Zeitung):

https://www.faz.net/aktuell/wissen/weltraum/esa-satellit-muss-musks-starlink-satellit-ausweichen-16366503.html (https://www.faz.net/aktuell/wissen/weltraum/esa-satellit-muss-musks-starlink-satellit-ausweichen-16366503.html)

IMHO, his statements are balanced and reasonable.  No bashing that I can perceive.  He argues that new procedures -- largely automated and autonomous -- need to be discussed and agreed upon, because such incidents are bound to become increasingly frequent.
Did he discuss that ESA is seeking funding for just such a system?
No he wasn't asked and it wasn't relevant.

I've used DeepL to provide a translation of the final paragraph:
Quote
I think that in the next two to three years we should have technical solutions that make our work much easier. Communication protocols, automatic decisions based on machine learning. Perhaps also the possibility of reaching the satellite at any time and not just when it is flying over a ground station, so that we can react more flexibly. Our proposal is to demonstrate by 2023 that a satellite makes a decision after a collision warning, votes and then evades autonomously. Autonomous does not mean that it does everything on board, which of course requires contact with the ground. But at the moment we are not in a position to do so. Many experts are paid to stay awake around the clock and assess the situation. And that is no longer manageable when we soon have five times the number of satellites.

Translated with www.DeepL.com/Translator

Seems all sensible stuff.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Draggendrop on 09/03/2019 07:56 pm
So the main problem I see is a lot of miscommunication and a lack of cooperation between SpaceX and ESA.

If SpaceX wants Starlink to be successfull they should really start to consider the concerns of the other players. There will be new rules in the future, just because the amount of new satellites is too big. And if you want these regulations be in favour of your plans, you need the others to trust you.

So it should be in SpaceX own interest to have a better relation with ESA (and the scientific community in general) in the future.

In this instance I believe ESA could have handled this in a more professional manner.  Twitter is not the venue to use for a general avoidance maneuver or to use this situation for other means without direct dialogue with those in a conflicting situation.

oops...been ninja'd
Twitter was used to report the news after the event.

SpaceX have admitted that they were partly at fault:
Quote
A SpaceX spokesperson said a bug in its on-call operating system prevented the team from seeing that the risk of a collision with the ESA craft may have increased.

“Had the Starlink operator seen the correspondence, we would have coordinated with ESA to determine best approach with their continuing with their manoeuvre or our performing a manoeuvre,” the spokesperson said.

This is a bit like pulling out of a junction without seeing another car, with both having equal priority, but the other driver has plenty of time to avoid you, and does so. A quick "sorry" is the end of the problem.

Except in this case .... some sort of procedures will be needed to support 10s of thousands of satellites in orbit. For everyone's sake. 

By the way, who is responsible for warning SpaceX about collision threats? Is this the USAF? Do they provide this as a service to all satellite operators?

Yes twitter was used to report the news after the event. That is not the issue when one has hindsight.

This issue erupted in an incoherent manner with false assumptions by a twitter handle with information from a probably unauthorized individual. This then spread to a few articles. This went on for approximately 12 hours.

Only later did the dust settle but the point being...twitter was not the venue to use for an avoidance maneuver.

That is my opinion and others are welcome to theirs...we don't need this thread derailed so I am done with this until the next adventure occurs.

Thanks for your input though.
Title: Re: Starlink : General Discussion - Thread 2
Post by: AC in NC on 09/03/2019 08:01 pm
I'm a little surprised this problem isn't far more tractable than it seems on the surface based on how the principals are behaving.  Is there something that makes this anything other than a mathematics problem, even if that mathmatics problem requires an excessive number of FLOPS from the CPU hamsters?

It almost feels like they are calculating 1in1000 because they are arbitrarily introducing an artificial "sphere of uncertainty" which turns something they know is a non-collision intersection into one that might have some marginal chance of collision.

Seems strange.  Curious if knowledgeable folk know differently.
Title: Re: Starlink : General Discussion - Thread 2
Post by: envy887 on 09/03/2019 08:07 pm
I'm a little surprised this problem isn't far more tractable than it seems on the surface based on how the principals are behaving.  Is there something that makes this anything other than a mathematics problem, even if that mathmatics problem requires an excessive number of FLOPS from the CPU hamsters?

It almost feels like they are calculating 1in1000 because they are arbitrarily introducing an artificial "sphere of uncertainty" which turns something they know is a non-collision intersection into one that might have some marginal chance of collision.

Seems strange.  Curious if knowledgeable folk know differently.

I don't think computation is the issue. If every satellite had a GPS position feeding realtime data, the assessments could probably be done in short order on a typical workstation-class computer with very high accuracy.

The problem is getting that data from many operators at once, sending it to a central location in a reasonable time, then disseminating to all the operators. And also that debris isn't going to give you GPS locations, and debris is fy far the biggest share of objects and will be even if SpaceX launches 12,000 Starlinks.
Title: Re: Starlink : General Discussion - Thread 2
Post by: whitelancer64 on 09/03/2019 08:15 pm
I'm a little surprised this problem isn't far more tractable than it seems on the surface based on how the principals are behaving.  Is there something that makes this anything other than a mathematics problem, even if that mathmatics problem requires an excessive number of FLOPS from the CPU hamsters?

It almost feels like they are calculating 1in1000 because they are arbitrarily introducing an artificial "sphere of uncertainty" which turns something they know is a non-collision intersection into one that might have some marginal chance of collision.

Seems strange.  Curious if knowledgeable folk know differently.

Orbits can be somewhat chaotic. Drag is a very big factor and it's not a constant, it's a variable. The very high upper atmosphere of the Earth can be more or less dense by a considerable amount, depending largely on solar activity. So you can't make precise orbital predictions very far out. This is more true the lower the altitude of the satellite (the more it is influenced by Earth's atmosphere).

So you have to work with probability, and 1-in-1000 is not a bad threshold to work with. As mentioned, there is some uncertainty in orbital tracking, in the time delay to get that information out, and variability in the orbit itself.
Title: Re: Starlink : General Discussion - Thread 2
Post by: OTV Booster on 09/03/2019 08:31 pm
Looking at the orbital parameters of Aeolus, the satellite it intercepted was 44278 aka 2019-029AV, currently in a 346km by 311km orbit (as of the last TLE), the only satellite with the perigee lower than the Aeolus mean orbital altitude, that currently is in a 314km by 308 km orbit.

Is it still settling into its final orbit? I’d assume so if it has a unique perigee. Last one or are others still raising perigee?

Phil
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 09/03/2019 08:51 pm
Looking at the orbital parameters of Aeolus, the satellite it intercepted was 44278 aka 2019-029AV, currently in a 346km by 311km orbit (as of the last TLE), the only satellite with the perigee lower than the Aeolus mean orbital altitude, that currently is in a 314km by 308 km orbit.

Is it still settling into its final orbit? I’d assume so if it has a unique perigee. Last one or are others still raising perigee?

Phil

It is lower than the deployment orbit, presumably it is one of the satellites they are using for deorbit testing.
Title: Re: Starlink : General Discussion - Thread 2
Post by: OTV Booster on 09/03/2019 09:12 pm
Going by info in the updates thread it looks like ESA is miffed at SpaceX for "refusing" to move first.

https://forum.nasaspaceflight.com/index.php?topic=48135.msg1987952#msg1987952 (https://forum.nasaspaceflight.com/index.php?topic=48135.msg1987952#msg1987952)

No idea who is in the "right" here, if there is even a right of way system worked out yet.

We better get on that. It's only going to get more crowded up there.

On the water unpowered has right of way over powered, unmaneuverable has right of way over maneuverable, with some caveats. In aircraft personal experience is that nobody cares because everybody does everything they can to avoid contact. With surface vehicles there is a complex set of rules that dictate right of way in most situations but the reality is the driver buried in their phone has right of way followed by whoever has the most brass.

I think the OST calls for the parties to consult and cooperate. I’ll check on it

Phil
Title: Re: Starlink : General Discussion - Thread 2
Post by: Lar on 09/03/2019 09:18 pm
Did he discuss that ESA is seeking funding for just such a system?
No he wasn't asked and it wasn't relevant.
That he wasn't asked is, in my view, a journalistic oversight, because, again in my view, it's highly relevant. YMMV.
Quote

I've used DeepL to provide a translation of the final paragraph:
Quote
I think that in the next two to three years we should have technical solutions that make our work much easier. Communication protocols, automatic decisions based on machine learning. Perhaps also the possibility of reaching the satellite at any time and not just when it is flying over a ground station, so that we can react more flexibly. Our proposal is to demonstrate by 2023 that a satellite makes a decision after a collision warning, votes and then evades autonomously. Autonomous does not mean that it does everything on board, which of course requires contact with the ground. But at the moment we are not in a position to do so. Many experts are paid to stay awake around the clock and assess the situation. And that is no longer manageable when we soon have five times the number of satellites.

Translated with www.DeepL.com/Translator

Seems all sensible stuff.
Seems like he's advocating for the solution ESA is seeking funding for.

It's not wrong to seek funding. it IS wrong to try to cast aspersions by omission on other entities in order to make the issue seem graver than it is. Again, IMHO.
Title: Re: Starlink : General Discussion - Thread 2
Post by: OTV Booster on 09/03/2019 10:57 pm
Going by info in the updates thread it looks like ESA is miffed at SpaceX for "refusing" to move first.

https://forum.nasaspaceflight.com/index.php?topic=48135.msg1987952#msg1987952 (https://forum.nasaspaceflight.com/index.php?topic=48135.msg1987952#msg1987952)

No idea who is in the "right" here, if there is even a right of way system worked out yet.

We better get on that. It's only going to get more crowded up there.

On the water unpowered has right of way over powered, unmaneuverable has right of way over maneuverable, with some caveats. In aircraft personal experience is that nobody cares because everybody does everything they can to avoid contact. With surface vehicles there is a complex set of rules that dictate right of way in most situations but the reality is the driver buried in their phone has right of way followed by whoever has the most brass.

I think the OST calls for the parties to consult and cooperate. I’ll check on it

Phil

Just checked. The OST sez you’re responsible for your own hardware and if something bad is going to happen ya gotta talk with whoever it makes sense to talk to. I paraphrased a bit. Mostly general principals.

There are some other UN space agreements that I am less familiar with but I do believe get more specific on narrow issues. Seems like a reasonable venue for traffic rules. It’s not all that controversial an issue. Just need everybody on the same page.

Back to StarLink...
Title: Re: Starlink : General Discussion - Thread 2
Post by: Robotbeat on 09/04/2019 12:14 am
I’m impressed by the ESA representative in that German article.
Title: Re: Starlink : General Discussion - Thread 2
Post by: matthewkantar on 09/04/2019 01:01 am
I only caught the tail end of it, but this issue made NPR this evening.
Title: Re: Starlink : General Discussion - Thread 2
Post by: dglow on 09/04/2019 05:02 am
Am I the only one here thinking that creating an automated satellite coordination/avoidance system would also introduce a terrifying vulnerability as it became the mother of all hacking targets?
Title: Re: Starlink : General Discussion - Thread 2
Post by: Asteroza on 09/04/2019 05:42 am
Am I the only one here thinking that creating an automated satellite coordination/avoidance system would also introduce a terrifying vulnerability as it became the mother of all hacking targets?

Navigation has always been the responsibility of the operator/owner for moving vehicles. Standardizing something like a TCAS algorithm (ascending node UP/left, descending node DOWN/right), and having multiple TLE clearinghouses that an operator sucks in data from allows for TLE data crosschecks. SpaceX still basically uploads an abridged TLE model to Starlink, which basically needs to decide based on last received model (in case of comms failure), so SpaceX as the operator has their own responsibility to make sure their final uploaded model is clean. I imagine it would be the same with other megaconstellation operators as they have the manpower. For smaller fleets and single sat operators, they may be downloading a merged abridged model from a national TLE clearinghouse to use as is, which is a single point of failure for those operators.

Perhaps the somewhat more relevant issue is, for autonomous maneuver, sats don't currently have the equivalent of an AIS or ADS-B beacon for other sats to detect their intentions directly (with some similarity for vehicle-to-vehicle P2P communication for cars aka V2V to share sensor and motion planning data as part of self driving regulations). Even if they had beacons that showed intent, there's the related issue that if you have two sats with only electric thrusters, could they detect the other's beacon early enough to maneuver enough to avoid a collision?
Title: Re: Starlink : General Discussion - Thread 2
Post by: Semmel on 09/04/2019 07:29 am
Interview on "space safety" with ESA expert Holger Krag was just published by German quality daily (Frankfurter Allgemeine Zeitung):

https://www.faz.net/aktuell/wissen/weltraum/esa-satellit-muss-musks-starlink-satellit-ausweichen-16366503.html (https://www.faz.net/aktuell/wissen/weltraum/esa-satellit-muss-musks-starlink-satellit-ausweichen-16366503.html)

IMHO, his statements are balanced and reasonable.  No bashing that I can perceive.  He argues that new procedures -- largely automated and autonomous -- need to be discussed and agreed upon, because such incidents are bound to become increasingly frequent.
Did he discuss that ESA is seeking funding for just such a system?

He said that ESA is working on such a system. The funding part was not said. Here is the relevant part:

Quote
Die Art und Weise, wie diese Koordination heute funktioniert, ist – kann man fast sagen – primitiv, denn das funktioniert per E-Mail und per Telefon.

[...]

Wie sähe eine Lösung aus?

Der Prozess der Absprache muss modernisiert und professioneller werden. Wir werden jetzt unseren Mitgliedsstaaten ein Programm vorschlagen, „Space Safety“, das auf der Esa-Ministerratskonferenz im November vorgestellt wird, wo wir auch Lösungen zu diesem Thema auf den Tisch legen wollen.

My translation (not word for word):

Quote
Today, the communication in case of a collision warning is, one could almost say, primitive. It works via e-mail and telephone.

[...]

How would a solution look like?

The process of coordination must become modern and professional. We will propose a new program to our member states called 'Space Safety', which will be discussed on the ESA conference of secretary (loose translation) in November. There we will suggest this system as a solution to the topic of traffic management.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Alastor on 09/04/2019 08:15 am
He said that ESA is working on such a system. The funding part was not said. Here is the relevant part:

My translation (not word for word):

Quote
Today, the communication in case of a collision warning is, one could almost say, primitive. It works via e-mail and telephone.

[...]

How would a solution look like?

The process of coordination must become modern and professional. We will propose a new program to our member states called 'Space Safety', which will be discussed on the ESA conference of secretary (loose translation) in November. There we will suggest this system as a solution to the topic of traffic management.
Bold mine.

You may not be aware of how ESA works, but it is essentially equivalent to NASA. So an ESA representative saying "We will propose a new program to our member states" is roughly equivalent to NASA saying "We will propose a new program to congress".
So in the extract you quoted, he is essentially saying that they are seeking funding to develop a solution to this problem.

Now the issue is not that they have a project on the topic nor that they are seeking funding for it. It's not "they are making a fuss about it just to get funding" as some here seem to believe.
The very fact that they are proposing a program on this topic means that they are being genuinely worried about this issue and think that it is worth investing a lot of money (that they could certainly use for other things) on this.

Now the real issue with this kind of stuff is that you can invest all the money you want on developing a solution, it is useless if you don't get an international agreement on using it. Hence why they are trying to raise awareness on the issue. If international partners don't care about this, you're getting nowhere.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Barley on 09/04/2019 05:19 pm
Standardizing something like a TCAS algorithm (ascending node UP/left, descending node DOWN/right),
Standardized rules are good.

But simplistic rules of thumb (e.g. ascending node UP/left, descending node DOWN/right) are used when you have a control loop where humans have to act quickly.  In this case if humans need to act quickly that is a design flaw that needs to be fixed.

Also it's entirely possible for two ascending satellites to be on a collision course so the proposed rule of thumb would need to be more complex, which defeats the purpose.
Title: Re: Starlink : General Discussion - Thread 2
Post by: envy887 on 09/04/2019 06:15 pm
Air Force statement to the Verge with additional details:

Quote
Typically, the United States Air Force, which monitors space traffic, will issue warnings, or conjunction data messages (CDMs), if there is a high probability of a collision. The threshold for sending out a warning is when there is a probability of more than 1 in 10,000 of an impact. The Air Force’s 18th Space Control Squadron, or 18 SPCS, which issues these warnings, confirmed to The Verge that it sent nine updates to both ESA and SpaceX in the 72 hours leading up to the closest approach of the two satellites.

A spokesperson also noted that both SpaceX and ESA have an agreement with US Space Command that allows them to receive additional advanced warnings of these threats up to seven days beforehand (rather than the standard three days). “Both ESA and SpaceX also submit their [data] to 18 SPCS on a regular basis so they received additional CDMs that supported possible maneuver planning,” a spokesperson for Air Force Space Command said in a statement to The Verge. “Totaling messages for this event, ESA received 32 CDMs, and SpaceX received 29.” SpaceX did not say if the company received these alerts from the Air Force or if the bug prevented the company from seeing them. The Air Force acknowledged that the CDMs are sent via email.

https://www.theverge.com/2019/9/3/20847243/spacex-starlink-satellite-european-space-agency-aeolus-conjunction-space-debris
Title: Re: Starlink : General Discussion - Thread 2
Post by: FutureSpaceTourist on 09/05/2019 07:48 pm
https://youtu.be/RJcnQq8XDoY
Title: Re: Starlink : General Discussion - Thread 2
Post by: OTV Booster on 09/05/2019 08:07 pm
Standardizing something like a TCAS algorithm (ascending node UP/left, descending node DOWN/right),
Standardized rules are good.

But simplistic rules of thumb (e.g. ascending node UP/left, descending node DOWN/right) are used when you have a control loop where humans have to act quickly.  In this case if humans need to act quickly that is a design flaw that needs to be fixed.

Also it's entirely possible for two ascending satellites to be on a collision course so the proposed rule of thumb would need to be more complex, which defeats the purpose.

In rethinking several pucker situations I’ve had in choppers the immediate reflex is for the low craft to go lower and the high guy to go higher. The aircraft to the right breaks right and the left breaks left although differences in turn performance can make this sub optimal but better than nothing. One will dive and break one way and one will climb and break the other way. The only situation not covered is dead on head to head which if you have very precise tracking data will ALMOST never happen. For this a random generator throwing both craft in a random direction reduces the odd to some non zero but VERY VERY low chance of collision. Repeat random as needed.

Seems like a starting point for traffic rules.

Phil
Title: Re: Starlink : General Discussion - Thread 2
Post by: rsdavis9 on 09/05/2019 08:18 pm
It seems to me. That there is 2 classes of objects. Ones that can move and those that can't or wont.
If all objects that can move increased there orbital TLE'S precision and published them hourly them almost all potential collisions with 2 moveable objects would be in the we don't care level of what did elon say industry standard 1 in 10000.

Then autonomous avoidance of effectively space junk would be easier because we "know" only one will do the avoidance maneuver. 

Of course if we have a higher precision catalog of all objects(timely and precise) then maneuvers will be almost eliminated.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Lar on 09/05/2019 09:08 pm
It seems to me. That there is 2 classes of objects. Ones that can move and those that can't or wont.
If all objects that can move increased there orbital TLE'S precision and published them hourly them almost all potential collisions with 2 moveable objects would be in the we don't care level of what did elon say industry standard 1 in 10000.

Then autonomous avoidance of effectively space junk would be easier because we "know" only one will do the avoidance maneuver. 

Of course if we have a higher precision catalog of all objects(timely and precise) then maneuvers will be almost eliminated.

let's take general collision avoidance to our general collision avoidance thread, ok?

https://forum.nasaspaceflight.com/index.php?topic=48954
Title: Re: Starlink : General Discussion - Thread 2
Post by: cro-magnon gramps on 09/05/2019 10:40 pm
I saw a video on YouTube announcing that Starlink has applications for 4 launches this fall..
found this reference on another site...
https://forum.nasaspaceflight.com/index.php?topic=45440.msg1986759#msg1986759

previous to today, I was aware of 2 launches, in October and November... and 7 more in 2020, before July, and 7 more after that, before the end of the year.

Is this a change in the number of launches or is this moving the given number of launches to the left... something almost unheard of in space launches...
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 09/06/2019 03:48 am
I saw a video on YouTube announcing that Starlink has applications for 4 launches this fall..
found this reference on another site...
https://forum.nasaspaceflight.com/index.php?topic=45440.msg1986759#msg1986759

previous to today, I was aware of 2 launches, in October and November... and 7 more in 2020, before July, and 7 more after that, before the end of the year.

Is this a change in the number of launches or is this moving the given number of launches to the left... something almost unheard of in space launches...

SpaceX filed paperwork that would allow them to do up to four launches this year.  That doesn't necessarily mean they will.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Barley on 09/06/2019 06:43 am
Standardizing something like a TCAS algorithm (ascending node UP/left, descending node DOWN/right),
Standardized rules are good.

But simplistic rules of thumb (e.g. ascending node UP/left, descending node DOWN/right) are used when you have a control loop where humans have to act quickly.  In this case if humans need to act quickly that is a design flaw that needs to be fixed.

Also it's entirely possible for two ascending satellites to be on a collision course so the proposed rule of thumb would need to be more complex, which defeats the purpose.

In rethinking several pucker situations I’ve had in choppers the immediate reflex is for the low craft to go lower and the high guy to go higher. The aircraft to the right breaks right and the left breaks left although differences in turn performance can make this sub optimal but better than nothing. One will dive and break one way and one will climb and break the other way. The only situation not covered is dead on head to head which if you have very precise tracking data will ALMOST never happen. For this a random generator throwing both craft in a random direction reduces the odd to some non zero but VERY VERY low chance of collision. Repeat random as needed.

Seems like a starting point for traffic rules.

Phil
It's not the same.   The time and distance scales are completely different.

The warning is the result of a mathematical calculation about an object that you can't see, thousands of km away with many minutes or days of warning.  You know what it is and where it will be (or you don't know there will be a collision at all.)  Reflective action is not required.  You can take minutes (possibly thousands of minutes) to figure out the best course and try to communicate.  If you can communicate or the object has characteristics or intentions listed in whatever data base is being used to foresee the collision these can be taken into account.

If you get to the pucker point with an unknown object looming in a view port you've already lost. 

Computers don't have reflexes in anyway comparable to humans.  Trying to get them to act like humans is very difficult, it's usually much easier to use a different solution that plays to their strengths, such as using a detailed checklist thousands of items long requiring millions of calculations.  The last few items on the list might resemble the actions you suggest, but these should not be the meat of the algorithm.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Rondaz on 09/07/2019 05:24 pm
Inter-satellite laser link updatehttps://cis471.blogspot.com/2019/09/inter-satellite-laser-link-update.html
Making cost-effective ISLLs for LEO sats is harder than @elonmusk & others thought, but production models are on the horizon & will improve over time.

https://twitter.com/larrypress/status/1170365889360752640
Title: Re: Starlink : General Discussion - Thread 2
Post by: OTV Booster on 09/07/2019 05:58 pm

In rethinking several pucker situations I’ve had in choppers the immediate reflex is for the low craft to go lower and the high guy to go higher. The aircraft to the right breaks right and the left breaks left although differences in turn performance can make this sub optimal but better than nothing. One will dive and break one way and one will climb and break the other way. The only situation not covered is dead on head to head which if you have very precise tracking data will ALMOST never happen. For this a random generator throwing both craft in a random direction reduces the odd to some non zero but VERY VERY low chance of collision. Repeat random as needed.

Seems like a starting point for traffic rules.

Phil
It's not the same.   The time and distance scales are completely different.

The warning is the result of a mathematical calculation about an object that you can't see, thousands of km away with many minutes or days of warning.  You know what it is and where it will be (or you don't know there will be a collision at all.)  Reflective action is not required.  You can take minutes (possibly thousands of minutes) to figure out the best course and try to communicate.  If you can communicate or the object has characteristics or intentions listed in whatever data base is being used to foresee the collision these can be taken into account.

If you get to the pucker point with an unknown object looming in a view port you've already lost. 

Computers don't have reflexes in anyway comparable to humans.  Trying to get them to act like humans is very difficult, it's usually much easier to use a different solution that plays to their strengths, such as using a detailed checklist thousands of items long requiring millions of calculations.  The last few items on the list might resemble the actions you suggest, but these should not be the meat of the algorithm.

Barley, I posted a response in:
https://forum.nasaspaceflight.com/index.php?topic=48954 (https://forum.nasaspaceflight.com/index.php?topic=48954)
As per Lar’s request.

Lar, see? I’m trying to play nice. Sometimes it’s just sooo hard.

Phil

Edit: LAarrr! I can’t get the quote right. grumble, grumble.

Fixed the quote. Usually when there are problems it is an extra stray (or missing) [ or ] 
In this case it was a missing ]
Title: Re: Starlink : General Discussion - Thread 2
Post by: FlattestEarth on 09/07/2019 09:46 pm
https://spacenews.com/spacex-says-more-starlink-orbits-will-speed-service-reduce-launch-needs/
Title: Re: Starlink : General Discussion - Thread 2
Post by: Rondaz on 09/07/2019 10:25 pm
Now @SpaceX wants to switch the first phase to sats in 72 orbital planes. Wider, less dense coverage. Faster deployment. Probably no ISLLs? http://SpaceNews.com https://shar.es/aXjSBH @ArthurSauzay @Megaconstellati @cashel @MarkJHandley @OscarVisiedo  They need to plan ahead..

https://twitter.com/larrypress/status/1170449279376216065
Title: Re: Starlink : General Discussion - Thread 2
Post by: Rondaz on 09/07/2019 10:26 pm
[email protected]' latest filing with the @FCC seeking to increase orbital planes for #Starlink from 24 to 72 (file# SAT-MOD-20190830-00087) is available at:https://licensing.fcc.gov/cgi-bin/ws.exe/prod/ib/forms/attachment_menu.hts?id_app_num=131512&acct=599269&id_form_num=15&filing_key=-436235

https://twitter.com/Megaconstellati/status/1170456710110203904
Title: Re: Starlink : General Discussion - Thread 2
Post by: Rondaz on 09/08/2019 12:19 pm
As @TMFAssociates points out, it's remarkable how @SpaceX proposed a new @FCC processing round reviewing all #megaconstellations after @amazon's filings for #ProjectKuiper but believes its desired fundamental change in orbit geometries doesn't require such

https://twitter.com/Megaconstellati/status/1170656427268067328
Title: Re: Starlink : General Discussion - Thread 2
Post by: soltasto on 09/08/2019 02:37 pm
Quote
fundamental change in orbit geometries

Looks like they don't know the meaning of that...

SpaceX is asking the FCC to do a new processing round for satellites in completely new orbital shells, while the new Orbital planes SpaceX is asking for are contained in the same shell.

The comparison would have been fine if compared to the SpaceX VLEO constellation.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Ed on 09/08/2019 05:03 pm
Is there any indication how many sats will be on Starlink 1.0 flights?
Recent announcements with 22 per plane on three planes might indicate at least 66.
But what about one or two spares per plane.

Ed
Title: Re: Starlink : General Discussion - Thread 2
Post by: Lars-J on 09/08/2019 07:29 pm
Is there any indication how many sats will be on Starlink 1.0 flights?
Recent announcements with 22 per plane on three planes might indicate at least 66.
But what about one or two spares per plane.

Ed

No, I don’t think so. It seems pretty clear that the last flight was maxed out. (In payload mass)
Title: Re: Starlink : General Discussion - Thread 2
Post by: Robotbeat on 09/08/2019 08:31 pm
@TMFAssociates is, objectively, a SpaceX troll. Worth keeping that in mind.
Title: Re: Starlink : General Discussion - Thread 2
Post by: meekGee on 09/08/2019 09:59 pm
Is there any indication how many sats will be on Starlink 1.0 flights?
Recent announcements with 22 per plane on three planes might indicate at least 66.
But what about one or two spares per plane.

Ed

No, I don’t think so. It seems pretty clear that the last flight was maxed out. (In payload mass)
Was it?  Or was it just the heaviest payload they carried to date?
Title: Re: Starlink : General Discussion - Thread 2
Post by: guckyfan on 09/09/2019 06:19 am
Was it?  Or was it just the heaviest payload they carried to date?

They carried the first batch to above the ISS level, I understand at request of NASA. How much difference would it make if they carry them only to 250km? It should also make for faster precession into their different planes.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Ed on 09/09/2019 07:23 am
Is there any indication how many sats will be on Starlink 1.0 flights?
Recent announcements with 22 per plane on three planes might indicate at least 66.
But what about one or two spares per plane.

Ed

No, I don’t think so. It seems pretty clear that the last flight was maxed out. (In payload mass)
Was it?  Or was it just the heaviest payload they carried to date?

I just would find it a bit odd if SpaceX would not aim to fill each plane consistently with one falcon launch.
Migrating sats from other planes is time consuming and needs extra effort.

I think 72 sats 3 x (22 + 2 spares) per launch would be great,
but this is only my uneducated wild guess.

The whether this this achievable with Falcon reuse remains to be seen.

Filling two planes and one plane only half and then complete it with another lauch might be the next best thing. This also works with the original number of 60 sats per launch.

Hence my original question.

Ed
Title: Re: Starlink : General Discussion - Thread 2
Post by: speedevil on 09/09/2019 10:39 am
I just would find it a bit odd if SpaceX would not aim to fill each plane consistently with one falcon launch.
Migrating sats from other planes is time consuming and needs extra effort.
If we assume the stack is stable with half of them deployed, doing a 600m/s burn uses up 10 satellites worth of delta-v in doing a 5 degree plane change.
This lets you drop off 20 in one orbit, and 30 in another.

Title: Re: Starlink : General Discussion - Thread 2
Post by: Ed on 09/09/2019 11:36 am
I just would find it a bit odd if SpaceX would not aim to fill each plane consistently with one falcon launch.
Migrating sats from other planes is time consuming and needs extra effort.
If we assume the stack is stable with half of them deployed, doing a 600m/s burn uses up 10 satellites worth of delta-v in doing a 5 degree plane change.
This lets you drop off 20 in one orbit, and 30 in another.

Nice idea.
How about 25 into one plane and 25 into another.
Filling two with spares.

However SpaceX spoke in its recent FCC about transporting sats into three planes with one launch.
Title: Re: Starlink : General Discussion - Thread 2
Post by: speedevil on 09/09/2019 12:21 pm
I just would find it a bit odd if SpaceX would not aim to fill each plane consistently with one falcon launch.
Migrating sats from other planes is time consuming and needs extra effort.
If we assume the stack is stable with half of them deployed, doing a 600m/s burn uses up 10 satellites worth of delta-v in doing a 5 degree plane change.
This lets you drop off 20 in one orbit, and 30 in another.

Nice idea.
How about 25 into one plane and 25 into another.
Filling two with spares.

However SpaceX spoke in its recent FCC about transporting sats into three planes with one launch.

If we assume a purely propulsive ion engine manoever to change planes, it will take much of a year, based on the observed performance of the satellites.
If as I suspect, they have in fact fitted a ~200W, not ~3000W ion engine to the first launch, for ~10kg more mass, they can get ~10* the acceleration, or be able to move one plane in around a month - assuming they are not limited on production of these.

Masswise, this would be a wash, assuming an injection at ~430km (to miss ISS), with a transit to 550km, the cost of additional ion engine mass is equaled by propellant saving on S2.
Orbit raising would be only several days.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Semmel on 09/09/2019 01:33 pm
Speedevil, I think its very unlikely that they perform plane change maneuvers. Its far more likely that they distribute the sats using precession. Thats how everybody else (i.e. sun synchronous sats) do it.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 09/09/2019 02:55 pm
In their recent filing SpaceX said they want 22 satellites per plane, they would drift the satellites between planes, and deployment orbit would be 350km.  I would guess they use that deployment orbit for the next launches regardless of whether the change to the number of planes gets approved or not.  I would not assume they will launch a full set of 22 for each plane they're targeting right now.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Semmel on 09/09/2019 07:40 pm
In their recent filing SpaceX said they want 22 satellites per plane, they would drift the satellites between planes, and deployment orbit would be 350km.  I would guess they use that deployment orbit for the next launches regardless of whether the change to the number of planes gets approved or not.  I would not assume they will launch a full set of 22 for each plane they're targeting right now.

Thats my understanding as well. More planes that have a smaller angle difference, which makes populating multiple planes using precession (or drift) with one launch more viable and faster than before.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Barley on 09/09/2019 09:29 pm
The discussion of whether or not to use precession for plane changes without figuring out how long it would take seems futile.

In another thread I wrote the following, can anybody confirm or refute my numbers?  Then we can argue if 21 or 41 days is a long time or a short time.

By my calculation.

For circular orbits with 53degree inclination the difference in precession between 450km and 550km is 0.23degrees/day.  Between 450km and 1200km it's 1.44degrees/day.  Fast enough to be useful, slow enough to be annoying.

You can speed up the precession by flying lower, and might want to do that for replacements.  I'm not sure how low you can go, but 300km v. 550km gets you about 0.61degrees per day.
Title: Re: Starlink : General Discussion - Thread 2
Post by: speedevil on 09/09/2019 09:34 pm
The discussion of whether or not to use precession for plane changes without figuring out how long it would take seems futile.

In another thread I wrote the following, can anybody confirm or refute my numbers?  Then we can argue if 21 or 41 days is a long time or a short time.

By my calculation.

For circular orbits with 53degree inclination the difference in precession between 450km and 550km is 0.23degrees/day.  Between 450km and 1200km it's 1.44degrees/day.  Fast enough to be useful, slow enough to be annoying.

You can speed up the precession by flying lower, and might want to do that for replacements.  I'm not sure how low you can go, but 300km v. 550km gets you about 0.61degrees per day.

This is my understanding too. It's in the realm IMO that neither using precession, or using thrust is clearly ridiculous, and which is preferred may be dominated by other operational constraints.
Title: Re: Starlink : General Discussion - Thread 2
Post by: envy887 on 09/09/2019 11:39 pm
The discussion of whether or not to use precession for plane changes without figuring out how long it would take seems futile.

In another thread I wrote the following, can anybody confirm or refute my numbers?  Then we can argue if 21 or 41 days is a long time or a short time.

By my calculation.

For circular orbits with 53degree inclination the difference in precession between 450km and 550km is 0.23degrees/day.  Between 450km and 1200km it's 1.44degrees/day.  Fast enough to be useful, slow enough to be annoying.

You can speed up the precession by flying lower, and might want to do that for replacements.  I'm not sure how low you can go, but 300km v. 550km gets you about 0.61degrees per day.

The upcoming launches are using a lower insertion orbit. I think it's 350 km? That will speed precession compared to the 440 km insertion on the v0.9 flight.
Title: Re: Starlink : General Discussion - Thread 2
Post by: jpo234 on 09/10/2019 09:14 pm
https://spacenews.com/spacex-plans-24-starlink-launches-next-year/

24 Starlink launches next year.
Title: Re: Starlink : General Discussion - Thread 2
Post by: ZachF on 09/10/2019 09:14 pm
SpaceX targeting 24 Starlink launches next year:

https://spacenews.com/spacex-plans-24-starlink-launches-next-year/ (https://spacenews.com/spacex-plans-24-starlink-launches-next-year/)

I guess that means SpaceX is also targeting 40+ total launches next year...  8)
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 09/10/2019 09:49 pm
For that launch rate they'd have to be making at least 3 sats a day at their factory, that must be a pretty cool assembly line.
Title: Re: Starlink : General Discussion - Thread 2
Post by: meekGee on 09/10/2019 11:13 pm
https://spacenews.com/spacex-plans-24-starlink-launches-next-year/

24 Starlink launches next year.

More launches/year than some constellations have satellites.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Rondaz on 09/11/2019 12:39 am
SpaceX hopes for 24 Starlink launches in 2020 & up to 4 this year. http://SpaceNews.com https://shar.es/aXdTVl
That's > 1,000 sats they need for  "economic viability". Has the FCC approved the orbits? Probably no ISLLs.

https://twitter.com/larrypress/status/1171542311416680450
Title: Re: Starlink : General Discussion - Thread 2
Post by: Zed_Noir on 09/11/2019 01:22 am
For that launch rate they'd have to be making at least 3 sats a day at their factory, that must be a pretty cool assembly line.

Do folks think the Starlink spacecraft assembly line is going to be more like a car assembly line or a traditional spacecraft assembly line?

Come to think of it. After the Starlink constellation is up.  SpaceX will have pump out at least 2400 Starlinks spacecraft annually to maintain the constellation. :o

So either a big assembly plant (Starlink Megafactory) or several smaller assembly plants to supply the annual 2400+ spacecraft requirement. If SpaceX opts for the Megafactory, where will they sited it?
Title: Re: Starlink : General Discussion - Thread 2
Post by: ZachF on 09/11/2019 01:30 am
For that launch rate they'd have to be making at least 3 sats a day at their factory, that must be a pretty cool assembly line.

Do folks think the Starlink spacecraft assembly line is going to be more like a car assembly line or a traditional spacecraft assembly line?

Come to think of it. After the Starlink constellation is up.  SpaceX will have pump out at least 2400 Starlinks spacecraft annually to maintain the constellation. :o

So either a big assembly plant (Starlink Megafactory) or several smaller assembly plants to supply the annual 2400+ spacecraft requirement. If SpaceX opts for the Megafactory, where will they sited it?

In just a few years SpaceX may be the world's largest Launch services provider, Spacecraft manufacturer, satellite manufacturer, rocket engine manufacturer, rocket manufacturer, and satellite services provider.  :o

In some of these areas they may not only be largest, but larger than all of the others put together.

Pretty amazing since just a little over a decade ago they were basically launching hobby rockets.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 09/11/2019 01:53 am
Pretty amazing since just a little over a decade ago they were basically launching hobby rockets.

SpaceX was never launching hobby rockets.  Every one of their attempts, even though the first few weren't successful, was a full orbital launch vehicle.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Norm38 on 09/11/2019 11:00 am
All of a sudden there’s a lot riding on the next launch and the next batch of satellites. To spin up production as fast as they have to, with supply chain lead times, they have to prove and freeze the design now.
And I thought my project schedule is stressful...
Title: Re: Starlink : General Discussion - Thread 2
Post by: JamesH65 on 09/11/2019 12:07 pm
All of a sudden there’s a lot riding on the next launch and the next batch of satellites. To spin up production as fast as they have to, with supply chain lead times, they have to prove and freeze the design now.
And I thought my project schedule is stressful...

Will they freeze the design for all 24 launches? Or just have continuous/step improvements as they discover more?
Title: Re: Starlink : General Discussion - Thread 2
Post by: matthewkantar on 09/11/2019 01:01 pm
If you think the design of anything important at SpaceX will ever be "frozen," you have not been paying attention to how the company has functioned for more than a decade.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 09/11/2019 03:15 pm
If you think the design of anything important at SpaceX will ever be "frozen," you have not been paying attention to how the company has functioned for more than a decade.

Somewhat true, but there will need to be batches of some size for the major components.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Norm38 on 09/11/2019 03:52 pm
Musk did say that mass production is orders of magnitude harder than one-off or batch builds.  They have to be in mass production to build at these volumes, and that does mean freezing as much as possible.  Certainly it means formal change management and making improvements as formal new revisions.
Not doing it that way on a production line leads to build errors.
Title: Re: Starlink : General Discussion - Thread 2
Post by: meekGee on 09/11/2019 04:14 pm
"Mass production" is not black and white, and 1000s of units per year is not "mass" in any other industry - it's barely a pre-production run.

I bet anything that the satellites will continue to evolve, and the constellation will always be a mix of older and newer-more-capable satellites.

Title: Re: Starlink : General Discussion - Thread 2
Post by: oldAtlas_Eguy on 09/11/2019 08:33 pm
If SpaceX really does 24 launches in 2020 then those 72 planes will each be populated with ~ 22 / plane by EOY 2020. But by Aug 2020 SpaceX could have it's 1000 sats for initial commercial viability.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Nomadd on 09/11/2019 10:24 pm
 I'm going to talk to someone in Valdez about sat coverage in a few days. They're about 61N with a big honkin range of mountains to the south that limits geo availability. Has anyone created any sort of table to let people know about when Starlink sats might be available at different latitudes and antenna elevations? I've been too lazy to figure out how high the hills are from town when I'll just be able to measure them shortly. I know it's still guesswork with their deployment plans changing.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 09/11/2019 10:58 pm
This is what they said in their request to change the orbital configuration:
Quote
This adjustment will accelerate coverage to southern states
and U.S territories, potentially expediting coverage to the southern continental United States by
the end of the next hurricane season and reaching other U.S. territories by the following hurricane
season.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Ludus on 09/12/2019 08:01 am
If SpaceX really does 24 launches in 2020 then those 72 planes will each be populated with ~ 22 / plane by EOY 2020. But by Aug 2020 SpaceX could have it's 1000 sats for initial commercial viability.

When do you think they will transition to including the inter-satellite links? 
Title: Re: Starlink : General Discussion - Thread 2
Post by: woods170 on 09/12/2019 08:16 am
All of a sudden there’s a lot riding on the next launch and the next batch of satellites. To spin up production as fast as they have to, with supply chain lead times, they have to prove and freeze the design now.
And I thought my project schedule is stressful...

Will they freeze the design for all 24 launches? Or just have continuous/step improvements as they discover more?


The latter. Continuous improvements. Freezing the design is not the way SpaceX does things.
Title: Re: Starlink : General Discussion - Thread 2
Post by: guckyfan on 09/12/2019 08:27 am
When do you think they will transition to including the inter-satellite links?

If they don't now with the next launch I think they will build a fully operational constellation before they introduce them. Sats with laser links will be bigger and heavier, reducing the number of sats per Falcon launch.
Title: Re: Starlink : General Discussion - Thread 2
Post by: OTV Booster on 09/12/2019 06:37 pm
Without lateral coms each bird in the constellation will only act as an aggregation point for the users within its reception area and will need to downlink to a ground station for further transmission. This has been discussed but I’m not sure there been discussion of the implications.

In his FCC application for the new architecture Elon seems to be positioning as an alternative com for disasters and is focusing on the southern US. This sucks as a full business model but makes sense as a wedge to justify the new plan. Ok, he has a deadline to get something up and running or he doesn’t get the license. Is there any FCC criteria for minimum usability or is it just some number of sats that can transmit/receive?

I’m trying to figure out a viable business model without lateral coms and am drawing a blank. Can’t claim low latency. Can’t claim to serve sparsely populated areas unless they have a local ground station which means there has to be a backbone in place somewhere in the area. This makes the constellation a glorified cell tower.

The only thing I can come up with is hitting FCC numbers to secure the license and an R&D platform for the real constellation. Even if he hits the FCC numbers with a ‘minimally viable system’ and gets the license, without lateral coms he doesn’t have a product to sell.

So, I’ve been trying to figure out how the system currently in progress could evolve into a real system and that leads me to a question. Is it possible to salt some minimum number of sats WITH lateral coms into a higher orbit and make it work?

What I picture is something like this. Customer connects through a non-lateral sat which in turn connects to a ground station. The ground station connects to a lateral type sat which in turn relays through other lat sats and eventually to a ground station which either hits copper or a non-lat sat for the last mile. Latency would not be the absolute best but ok for most uses. More lat-sats would enter the system over time as would customer connect sats with lateral capability.

The lat sats could evolve into something different than the customer sats, aggregating traffic like the local ground stations which would eventually become redundant.  If placed on one of the higher orbits they would be positioned To do lateral coms to other far off lat sats keeping hops to a minimum and latency down. And they would do high volume downlink to data centers.

The down side is two different sat designs. As a counter, the customer connect sats would be relatively simple and inexpensive. The lateral com sats would be larger, heavier, more power hungry and more expensive, but fewer in number. Being on higher orbit they’d stick around longer. The most important plus this gives is an evolutionary path from what seems to me to be a lame system without ditching the early lame sats.


What alternatives can we come up with?


Phil






Title: Re: Starlink : General Discussion - Thread 2
Post by: Mandella on 09/12/2019 07:04 pm
Without lateral coms each bird in the constellation will only act as an aggregation point for the users within its reception area and will need to downlink to a ground station for further transmission. This has been discussed but I’m not sure there been discussion of the implications.

In his FCC application for the new architecture Elon seems to be positioning as an alternative com for disasters and is focusing on the southern US. This sucks as a full business model but makes sense as a wedge to justify the new plan. Ok, he has a deadline to get something up and running or he doesn’t get the license. Is there any FCC criteria for minimum usability or is it just some number of sats that can transmit/receive?

I’m trying to figure out a viable business model without lateral coms and am drawing a blank. Can’t claim low latency. Can’t claim to serve sparsely populated areas unless they have a local ground station which means there has to be a backbone in place somewhere in the area. This makes the constellation a glorified cell tower.

The only thing I can come up with is hitting FCC numbers to secure the license and an R&D platform for the real constellation. Even if he hits the FCC numbers with a ‘minimally viable system’ and gets the license, without lateral coms he doesn’t have a product to sell.

So, I’ve been trying to figure out how the system currently in progress could evolve into a real system and that leads me to a question. Is it possible to salt some minimum number of sats WITH lateral coms into a higher orbit and make it work?

What I picture is something like this. Customer connects through a non-lateral sat which in turn connects to a ground station. The ground station connects to a lateral type sat which in turn relays through other lat sats and eventually to a ground station which either hits copper or a non-lat sat for the last mile. Latency would not be the absolute best but ok for most uses. More lat-sats would enter the system over time as would customer connect sats with lateral capability.

The lat sats could evolve into something different than the customer sats, aggregating traffic like the local ground stations which would eventually become redundant.  If placed on one of the higher orbits they would be positioned To do lateral coms to other far off lat sats keeping hops to a minimum and latency down. And they would do high volume downlink to data centers.

The down side is two different sat designs. As a counter, the customer connect sats would be relatively simple and inexpensive. The lateral com sats would be larger, heavier, more power hungry and more expensive, but fewer in number. Being on higher orbit they’d stick around longer. The most important plus this gives is an evolutionary path from what seems to me to be a lame system without ditching the early lame sats.


What alternatives can we come up with?


Phil

The latency will still be quite low without lateral comms, at least regionally, and it won't be worse than ground internet for transoceanic distances. The idea as I understand it is that every satellite will be in reach of a ground station if it is near land, and that ground station links the satellite into terrestrial internet. So still far far better latency than bouncing everything off GEO.

What you lose without the interlink is reaching remote areas far from a ground station, most particularly mid ocean. Plus you lose the possibly ultra low latency from transoceanic communications.

It could still be quite a viable competitor to existing GEO satellite dishes in rural areas though, depending on pricing and bandwidth caps.
Title: Re: Starlink : General Discussion - Thread 2
Post by: speedevil on 09/12/2019 08:53 pm
I'm going to talk to someone in Valdez about sat coverage in a few days. They're about 61N with a big honkin range of mountains to the south that limits geo availability. Has anyone created any sort of table to let people know about when Starlink sats might be available at different latitudes and antenna elevations? I've been too lazy to figure out how high the hills are from town when I'll just be able to measure them shortly. I know it's still guesswork with their deployment plans changing.
I'm at 56N, so this is interesting to me.
The orbital inclination is 53 degrees.
If they are deployed at 550km, three degrees (~300km) north only puts them at around 60 degrees from the horizon, so I probably have coverage.

60N - 700km north of the northernmost ground track - means the satellite gets not much above 30 degrees - which is getting close to the point where the constellation may become extremely spotty.
(The official angle they can't provide service is 15 degrees above the horizon).

Any significant obstruction at all to the south is going to dramatically cut your likelyhood of continuous coverage..
Title: Re: Starlink : General Discussion - Thread 2
Post by: OTV Booster on 09/12/2019 10:28 pm
Without lateral coms each bird in the constellation will only act as an aggregation point for the users within its reception area and will need to downlink to a ground station for further transmission. This has been discussed but I’m not sure there been discussion of the implications.

In his FCC application for the new architecture Elon seems to be positioning as an alternative com for disasters and is focusing on the southern US. This sucks as a full business model but makes sense as a wedge to justify the new plan. Ok, he has a deadline to get something up and running or he doesn’t get the license. Is there any FCC criteria for minimum usability or is it just some number of sats that can transmit/receive?

I’m trying to figure out a viable business model without lateral coms and am drawing a blank. Can’t claim low latency. Can’t claim to serve sparsely populated areas unless they have a local ground station which means there has to be a backbone in place somewhere in the area. This makes the constellation a glorified cell tower.

The only thing I can come up with is hitting FCC numbers to secure the license and an R&D platform for the real constellation. Even if he hits the FCC numbers with a ‘minimally viable system’ and gets the license, without lateral coms he doesn’t have a product to sell.

So, I’ve been trying to figure out how the system currently in progress could evolve into a real system and that leads me to a question. Is it possible to salt some minimum number of sats WITH lateral coms into a higher orbit and make it work?

What I picture is something like this. Customer connects through a non-lateral sat which in turn connects to a ground station. The ground station connects to a lateral type sat which in turn relays through other lat sats and eventually to a ground station which either hits copper or a non-lat sat for the last mile. Latency would not be the absolute best but ok for most uses. More lat-sats would enter the system over time as would customer connect sats with lateral capability.

The lat sats could evolve into something different than the customer sats, aggregating traffic like the local ground stations which would eventually become redundant.  If placed on one of the higher orbits they would be positioned To do lateral coms to other far off lat sats keeping hops to a minimum and latency down. And they would do high volume downlink to data centers.

The down side is two different sat designs. As a counter, the customer connect sats would be relatively simple and inexpensive. The lateral com sats would be larger, heavier, more power hungry and more expensive, but fewer in number. Being on higher orbit they’d stick around longer. The most important plus this gives is an evolutionary path from what seems to me to be a lame system without ditching the early lame sats.


What alternatives can we come up with?


Phil

The latency will still be quite low without lateral comms, at least regionally, and it won't be worse than ground internet for transoceanic distances. The idea as I understand it is that every satellite will be in reach of a ground station if it is near land, and that ground station links the satellite into terrestrial internet. So still far far better latency than bouncing everything off GEO.

What you lose without the interlink is reaching remote areas far from a ground station, most particularly mid ocean. Plus you lose the possibly ultra low latency from transoceanic communications.

It could still be quite a viable competitor to existing GEO satellite dishes in rural areas though, depending on pricing and bandwidth caps.

Just about anything is better than bouncing to GEO.

So all it will do at first is cover the last mile, er last ~1000km. With an unknown cost for customer hardware, but guesses of around $200 or more, it doesn’t sound compelling unless the rates are great. Of course everybody seems to want to ditch their current provider so there is some hope.

IIRC The pics of ground stations show dish antennas. This would have to move to phased array for production units I expect. What would the footprint of a ground station be? I’m trying to figure out the economics of this. What you describe seems technically sound but I’m skeptical on the business case. It is admittedly an interim solution.

Still, once they roll out lateral sats they either ditch the old system, run two systems in parallel or have a plan to integrate them. The last two options would last until the legacy sats hit EOL.

Reality warning. If Elon depended on me for his economic forecasts he would now be a very successful shoe salesman.

Phil
Title: Re: Starlink : General Discussion - Thread 2
Post by: ninjaneer on 09/12/2019 11:44 pm
So all it will do at first is cover the last mile, er last ~1000km. With an unknown cost for customer hardware, but guesses of around $200 or more, it doesn’t sound compelling unless the rates are great. Of course everybody seems to want to ditch their current provider so there is some hope.

IIRC The pics of ground stations show dish antennas. This would have to move to phased array for production units I expect. What would the footprint of a ground station be? I’m trying to figure out the economics of this. What you describe seems technically sound but I’m skeptical on the business case. It is admittedly an interim solution.

Were I to bet on it, I'd wager ~$500 for the setup if it's the cheap phased array.  Still much lower than ~$1200 for a regular dish and $2000 for the 1.8m oversized edition.  Monthly packages may match ViaSat prices of $2/gb at first.

If they have to fall back like OneWeb and offer twin dishes to start, then I'd guess about $4000-$5000 for the setup, with each dish coming closer in size to RV in-motion dishes (~15 inch domes).

Nobody with terrestrial internet is going to jump unless they're a superfan with deep pockets.  I kind of feel bad for all the people who overhyped themselves.  I'm patiently waiting, though.
Title: Re: Starlink : General Discussion - Thread 2
Post by: freddo411 on 09/13/2019 12:48 am
Without lateral coms each bird in the constellation will only act as an aggregation point for the users within its reception area and will need to downlink to a ground station for further transmission. This has been discussed but I’m not sure there been discussion of the implications.

In his FCC application for the new architecture Elon seems to be positioning as an alternative com for disasters and is focusing on the southern US. This sucks as a full business model but makes sense as a wedge to justify the new plan. Ok, he has a deadline to get something up and running or he doesn’t get the license. Is there any FCC criteria for minimum usability or is it just some number of sats that can transmit/receive?

I’m trying to figure out a viable business model without lateral coms and am drawing a blank. Can’t claim low latency. Can’t claim to serve sparsely populated areas unless they have a local ground station which means there has to be a backbone in place somewhere in the area. This makes the constellation a glorified cell tower.

The only thing I can come up with is hitting FCC numbers ...

...

What alternatives can we come up with?



Yes, the initial, no interlinks sats mean that latency across the Atlantic or Pacific is no better than the routes in use today.

Yes, showing a working system to potential customers, investors and the Federal regulators is highly important, even if it is a loss leader.   

But, you have mis-estimate the utility of large swaths of North America being able to get high speed internet based upon the minimal constellation.  It will only take a minimum of 3 ground stations to serve all of the US (depending on usage).   There are many "fly over states" in rural areas where internet access is ludicrously expensive and very poorly implemented.   The RV market alone could be a significant start at a customer base. 
Title: Re: Starlink : General Discussion - Thread 2
Post by: ZChris13 on 09/13/2019 12:56 am
Without lateral coms each bird in the constellation will only act as an aggregation point for the users within its reception area and will need to downlink to a ground station for further transmission. This has been discussed but I’m not sure there been discussion of the implications.

In his FCC application for the new architecture Elon seems to be positioning as an alternative com for disasters and is focusing on the southern US. This sucks as a full business model but makes sense as a wedge to justify the new plan. Ok, he has a deadline to get something up and running or he doesn’t get the license. Is there any FCC criteria for minimum usability or is it just some number of sats that can transmit/receive?

I’m trying to figure out a viable business model without lateral coms and am drawing a blank. Can’t claim low latency. Can’t claim to serve sparsely populated areas unless they have a local ground station which means there has to be a backbone in place somewhere in the area. This makes the constellation a glorified cell tower.

The only thing I can come up with is hitting FCC numbers ...

...

What alternatives can we come up with?



Yes, the initial, no interlinks sats mean that latency across the Atlantic or Pacific is no better than the routes in use today.

Yes, showing a working system to potential customers, investors and the Federal regulators is highly important, even if it is a loss leader.   

But, you have mis-estimate the utility of large swaths of North America being able to get high speed internet based upon the minimal constellation.  It will only take a minimum of 3 ground stations to serve all of the US (depending on usage).   There are many "fly over states" in rural areas where internet access is ludicrously expensive and very poorly implemented.   The RV market alone could be a significant start at a customer base.
The amount of rural America even on the east coast (I am, in particular, thinking about North Carolina and upstate South Carolina) that doesn't have proper broadband access despite being only a few miles out of town is extreme.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Mandella on 09/13/2019 01:48 am
Without lateral coms each bird in the constellation will only act as an aggregation point for the users within its reception area and will need to downlink to a ground station for further transmission. This has been discussed but I’m not sure there been discussion of the implications.

In his FCC application for the new architecture Elon seems to be positioning as an alternative com for disasters and is focusing on the southern US. This sucks as a full business model but makes sense as a wedge to justify the new plan. Ok, he has a deadline to get something up and running or he doesn’t get the license. Is there any FCC criteria for minimum usability or is it just some number of sats that can transmit/receive?

I’m trying to figure out a viable business model without lateral coms and am drawing a blank. Can’t claim low latency. Can’t claim to serve sparsely populated areas unless they have a local ground station which means there has to be a backbone in place somewhere in the area. This makes the constellation a glorified cell tower.

The only thing I can come up with is hitting FCC numbers ...

...

What alternatives can we come up with?



Yes, the initial, no interlinks sats mean that latency across the Atlantic or Pacific is no better than the routes in use today.

Yes, showing a working system to potential customers, investors and the Federal regulators is highly important, even if it is a loss leader.   

But, you have mis-estimate the utility of large swaths of North America being able to get high speed internet based upon the minimal constellation.  It will only take a minimum of 3 ground stations to serve all of the US (depending on usage).   There are many "fly over states" in rural areas where internet access is ludicrously expensive and very poorly implemented.   The RV market alone could be a significant start at a customer base.
The amount of rural America even on the east coast (I am, in particular, thinking about North Carolina and upstate South Carolina) that doesn't have proper broadband access despite being only a few miles out of town is extreme.

Yep. If SpaceX can offer competitive rates and bandwidth caps as compared to big satellite I'll shift in a heart beat, and Elon is certainly betting that I won't be alone.

On the other hand, if you live in a metro area and have fiber or the like? Yeah, don't think you'll be too impressed.
Title: Re: Starlink : General Discussion - Thread 2
Post by: docmordrid on 09/13/2019 02:23 am
In the metro Detroit area most have the choice of  AT&T, LTE, Comcast or secondary cable carriers  using others infrastructure. Fiber is slowly going in. Very. Slowly.

Affordable? 😬

Rural? 😬😬

Fertile ground.
Title: Re: Starlink : General Discussion - Thread 2
Post by: space_snap828 on 09/13/2019 02:33 am
In the metro Detroit area most have the choice of  AT&T, LTE, Comcast or secondary cable carriers  using others infrastructure. Fiber is slowly going in. Very. Slowly.

Affordable? 😬

Rural? 😬😬

Fertile ground.

I've wondered if net neutrality enforcement is going to be unnecessary to enforce in the near future. With the introduction of high-speed satellite internet, every ISP now has to compete with internet service from the sky. The monopolies and duopolies they've enjoyed, that have allowed them to jack prices and treat data unfairly, are coming to an end.
Perhaps the market is solving the issue. We shall see.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 09/13/2019 02:37 am
The satellites won't be great competitors in densely populated areas.
Title: Re: Starlink : General Discussion - Thread 2
Post by: DaveH62 on 09/13/2019 02:48 am
I think they’ll do continuous improvement, but lock down each flight load of 72 satellites. Improved chipsets or solar panels or improved mechanicals and engines. By the time the constellation is complete the satellites will be completely upgraded, while possibly never undergoing a single major refresh.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 09/13/2019 02:53 am
72 satellites?  Where are you getting that from?
Title: Re: Starlink : General Discussion - Thread 2
Post by: OTV Booster on 09/13/2019 03:57 am
In the metro Detroit area most have the choice of  AT&T, LTE, Comcast or secondary cable carriers  using others infrastructure. Fiber is slowly going in. Very. Slowly.

Affordable? 😬

Rural? 😬😬

Fertile ground.

While listening to what ya’ll sayin, I’m trying to place myself into the internet consumer spectrum. Fifteen years on the road and everything I got came through my phone either straight or as a hotspot. And little time for much more than email and NSF lurking. Now that I’m retired I’ve been using a local ISP that started out local, got sold a time or three and is now part of a relatively small company with a presence in about five not so big markets in the Midwest.

I used the original local company for about a year before the lifestyle change. Never had any problems with the technical end but dealing with the front end was like dealing with the old ma bell. They were sphincters. This incarnation seems to be very business like and competent. Install was on time and later a dead router replaced no question. So I don’t feel the pain I hear about with the big boys.

With unlimited bandwidth (they throttle but I never get near the line) for $60/mo, star link would have to offer one hellava deal to make me look twice. I realize I’m atipical and am starting to see the attraction for a lot of rural areas, especially if the lower 48 can be covered by three (I’ll say 3-5) ground stations. If the price is right. And in a lot of cases even if the price is not quite so right.

Good thing Elon doesn’t listen to me. He’d be wasted as a shoe salesman.

Phil
Title: Re: Starlink : General Discussion - Thread 2
Post by: joek on 09/13/2019 04:22 am
I think they’ll do continuous improvement, but lock down each flight load of 72 satellites. Improved chipsets or solar panels or improved mechanicals and engines. By the time the constellation is complete the satellites will be completely upgraded, while possibly never undergoing a single major refresh.

The entire constellation is going to be refreshed approximately every 5 years, as that is the nominal orbital life of an individual satellite.  Whether the satellites themselves get upgraded as frequently is another question; I expect they will.

It allows Starlink to stay technologically fresh and competitive.  A virtuous cycle if you will... sustainable cheap launch allows frequent physical refresh... which allows frequent refresh of improvements (competitive capabilities, costs, etc.)... which is also demanded by satellite lifetime... which benefits from and requires sustainable cheap launch.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Barley on 09/13/2019 07:24 am
"Mass production" is not black and white, and 1000s of units per year is not "mass" in any other industry - it's barely a pre-production run.

I bet anything that the satellites will continue to evolve, and the constellation will always be a mix of older and newer-more-capable satellites.
There are plenty of things that are produced in 1000s of units per year.  Guessing a little about market size and market fragmentation: MRI machines, spectrophotometers, dental X-ray machines, class II lift trucks.  Niche products to some extent, but there are a lot of niche products.

So there's plenty of people who know how to do this.  The production lines are in between JPL and GM.   A lot more hand work and batch processing than you'll see in an auto plant, but a recognizable production line.  With good change management the lines are tolerant to many (but not all) incremental changes.
Title: Re: Starlink : General Discussion - Thread 2
Post by: woods170 on 09/13/2019 09:12 am
"Mass production" is not black and white, and 1000s of units per year is not "mass" in any other industry - it's barely a pre-production run.

I bet anything that the satellites will continue to evolve, and the constellation will always be a mix of older and newer-more-capable satellites.
There are plenty of things that are produced in 1000s of units per year.  Guessing a little about market size and market fragmentation: MRI machines, spectrophotometers, dental X-ray machines, class II lift trucks.  Niche products to some extent, but there are a lot of niche products.

So there's plenty of people who know how to do this.  The production lines are in between JPL and GM.   A lot more hand work and batch processing than you'll see in an auto plant, but a recognizable production line.  With good change management the lines are tolerant to many (but not all) incremental changes.

Yes. This.
Title: Re: Starlink : General Discussion - Thread 2
Post by: woods170 on 09/13/2019 09:21 am
In the metro Detroit area most have the choice of  AT&T, LTE, Comcast or secondary cable carriers  using others infrastructure. Fiber is slowly going in. Very. Slowly.

Affordable? 😬

Rural? 😬😬

Fertile ground.

While listening to what ya’ll sayin, I’m trying to place myself into the internet consumer spectrum. Fifteen years on the road and everything I got came through my phone either straight or as a hotspot. And little time for much more than email and NSF lurking. Now that I’m retired I’ve been using a local ISP that started out local, got sold a time or three and is now part of a relatively small company with a presence in about five not so big markets in the Midwest.

I used the original local company for about a year before the lifestyle change. Never had any problems with the technical end but dealing with the front end was like dealing with the old ma bell. They were sphincters. This incarnation seems to be very business like and competent. Install was on time and later a dead router replaced no question. So I don’t feel the pain I hear about with the big boys.

With unlimited bandwidth (they throttle but I never get near the line) for $60/mo, star link would have to offer one hellava deal to make me look twice. I realize I’m atipical and am starting to see the attraction for a lot of rural areas, especially if the lower 48 can be covered by three (I’ll say 3-5) ground stations. If the price is right. And in a lot of cases even if the price is not quite so right.

Good thing Elon doesn’t listen to me. He’d be wasted as a shoe salesman.

Phil

Starlink IMO is not going to get all that much foot on the ground in areas with great existing terrestrial internet infrastructure, such as major cities in the USA, Canada and Europe and densily populated countries like my home country the Netherlands (where cable is currently being outclassed by fibre).

Fortunately mankind lives all over the planet and most of the planet does not exist of major cities or countries like the Netherlands.

So Starlink will be interesting to a very substantial portion of the world's population.

And heck, it will even be interesting to the farmers just outside the village where I live given that the local ISPs in the Netherlands (such as KPN and Ziggo) are (once again) refusing to invest in "fibre to the farm".
Title: Re: Starlink : General Discussion - Thread 2
Post by: Tuna-Fish on 09/13/2019 09:34 am
Without lateral coms each bird in the constellation will only act as an aggregation point for the users within its reception area and will need to downlink to a ground station for further transmission.

...

Can’t claim to serve sparsely populated areas unless they have a local ground station which means there has to be a backbone in place somewhere in the area. This makes the constellation a glorified cell tower.

The second the sats are dense enough in the sky that each groundstation can always see more than one bird from the same plane (or alternatively, can always see sats from more than one plane), they no longer need backbone everywhere, they just need a groundstation with power, as they can bounce the message between groundstations and sats until it reaches somewhere with backbone access. The difference in cost of placing a disconnected groundstation within reach of every potential US customer to getting backbone access within reach of everyone is massive.
Title: Re: Starlink : General Discussion - Thread 2
Post by: meekGee on 09/13/2019 10:59 am
"Mass production" is not black and white, and 1000s of units per year is not "mass" in any other industry - it's barely a pre-production run.

I bet anything that the satellites will continue to evolve, and the constellation will always be a mix of older and newer-more-capable satellites.
There are plenty of things that are produced in 1000s of units per year.  Guessing a little about market size and market fragmentation: MRI machines, spectrophotometers, dental X-ray machines, class II lift trucks.  Niche products to some extent, but there are a lot of niche products.

So there's plenty of people who know how to do this.  The production lines are in between JPL and GM.   A lot more hand work and batch processing than you'll see in an auto plant, but a recognizable production line.  With good change management the lines are tolerant to many (but not all) incremental changes.
Of course there are small production lines...

But the lines are not the same as when making 10,000,000 TVs per year, and you'll find a lot more variance and ability to improve/fix things during the production runs.

All I was saying was that the fact SpaceX is making 1000s doesn't mean the design ias frozen and all satellites will be the same, as some people were suggesting.

Title: Re: Starlink : General Discussion - Thread 2
Post by: kevinof on 09/13/2019 11:54 am
Yes, agreed. Major cities are taken care of mostly, but once you get to rural locations there are vasts numbers that simply can't afford that "last mile/km".  This is where Starlink can get big wins if it can hit the right price point.

I'd love it on my boat - Have Iridium but it's expensive and slow. A high speed internet connection at a good price would be huge.

In the metro Detroit area most have the choice of  AT&T, LTE, Comcast or secondary cable carriers  using others infrastructure. Fiber is slowly going in. Very. Slowly.

Affordable? 😬

Rural? 😬😬

Fertile ground.

While listening to what ya’ll sayin, I’m trying to place myself into the internet consumer spectrum. Fifteen years on the road and everything I got came through my phone either straight or as a hotspot. And little time for much more than email and NSF lurking. Now that I’m retired I’ve been using a local ISP that started out local, got sold a time or three and is now part of a relatively small company with a presence in about five not so big markets in the Midwest.

I used the original local company for about a year before the lifestyle change. Never had any problems with the technical end but dealing with the front end was like dealing with the old ma bell. They were sphincters. This incarnation seems to be very business like and competent. Install was on time and later a dead router replaced no question. So I don’t feel the pain I hear about with the big boys.

With unlimited bandwidth (they throttle but I never get near the line) for $60/mo, star link would have to offer one hellava deal to make me look twice. I realize I’m atipical and am starting to see the attraction for a lot of rural areas, especially if the lower 48 can be covered by three (I’ll say 3-5) ground stations. If the price is right. And in a lot of cases even if the price is not quite so right.

Good thing Elon doesn’t listen to me. He’d be wasted as a shoe salesman.

Phil

Starlink IMO is not going to get all that much foot on the ground in areas with great existing terrestrial internet infrastructure, such as major cities in the USA, Canada and Europe and densily populated countries like my home country the Netherlands (where cable is currently being outclassed by fibre).

Fortunately mankind lives all over the planet and most of the planet does not exist of major cities or countries like the Netherlands.

So Starlink will be interesting to a very substantial portion of the world's population.

And heck, it will even be interesting to the farmers just outside the village where I live given that the local ISPs in the Netherlands (such as KPN and Ziggo) are (once again) refusing to invest in "fibre to the farm".
Title: Re: Starlink : General Discussion - Thread 2
Post by: JamesH65 on 09/13/2019 12:16 pm
Starlink IMO is not going to get all that much foot on the ground in areas with great existing terrestrial internet infrastructure, such as major cities in the USA, Canada and Europe and densily populated countries like my home country the Netherlands (where cable is currently being outclassed by fibre).

Fortunately mankind lives all over the planet and most of the planet does not exist of major cities or countries like the Netherlands.

So Starlink will be interesting to a very substantial portion of the world's population.

And heck, it will even be interesting to the farmers just outside the village where I live given that the local ISPs in the Netherlands (such as KPN and Ziggo) are (once again) refusing to invest in "fibre to the farm".

Exactly. You don't have to get far our of major conurbations to find the net access (and 4G) is very poor indeed, and that's in a relatively densely populated place like the UK. And someone mentioned they used mobile access and hotspots in a post above. But those hotspots need net access somehow, Starlink would be a great way of providing that in many places.

And, here in the UK, even in major conurbations you get areas with terrible terrestrial net access, and 4g is expensive for large amounts of data (netflix etc).
Title: Re: Starlink : General Discussion - Thread 2
Post by: wannamoonbase on 09/13/2019 03:13 pm
https://arstechnica.com/information-technology/2019/09/spacex-says-itll-deploy-satellite-broadband-across-us-faster-than-expected/

Interesting story.  3 planes per launch, will that mean use of the upper stage or will it rely on the krypton propulsion?
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 09/13/2019 03:14 pm
https://arstechnica.com/information-technology/2019/09/spacex-says-itll-deploy-satellite-broadband-across-us-faster-than-expected/

Interesting story.  3 planes per launch, will that mean use of the upper stage or will it rely on the krypton propulsion?

Is it really that hard to look back a couple days in this thread?
https://forum.nasaspaceflight.com/index.php?topic=48297.msg1990633#msg1990633
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 09/13/2019 05:07 pm
We need to start splitting up the Starlink discussion a little now that it's actually being built.  I stole a few recent posts to start a thread on alternate Starlink design/uses other than the LEO communications constellation.
SpaceX Starlink : Uses beyond just Earth communications (https://forum.nasaspaceflight.com/index.php?topic=49024.0)
Title: Re: Starlink : General Discussion - Thread 2
Post by: Barley on 09/13/2019 05:18 pm
The difference in cost of placing a disconnected groundstation within reach of every potential US customer to getting backbone access within reach of everyone is massive.
With a modest range of say 500 miles there is no technical need for disconnected ground stations.  Even the remote parts of western North Dakota can be served by ground stations in Billings or Fargo, or Denver or Winnipeg, were there are backbones.

Starlink may want to handle the backhaul themselves so they can negotiate more favorable peering agreements, but they don't have to unless there is massive collusion between many different geographically diverse internet companies.
Title: Re: Starlink : General Discussion - Thread 2
Post by: AC in NC on 09/13/2019 05:38 pm
There will be a non-negligible number of people that jump onboard Starlink earlier than makes sense.  Personally if the price wasn't ridiculous I might pay just to be on the bleeding edge (for once, not my typical approach) BUT without going all-in meaning I'd have a backup unlimited connection.

Could you have Starlink end-user base stations able to have the Starlink equipment leverage the latent capacity on the user's alternate network connection in order to expand Starlink's effective base-station capacity?

Sort of seems shady but I find the notion intriguing.

Off my rocker?
Title: Re: Starlink : General Discussion - Thread 2
Post by: oldAtlas_Eguy on 09/13/2019 05:42 pm
We need to start splitting up the Starlink discussion a little now that it's actually being built.  I stole a few recent posts to start a thread on alternate Starlink design/uses other than the LEO communications constellation.
SpaceX Starlink : Uses beyond just Earth communications (https://forum.nasaspaceflight.com/index.php?topic=49024.0)
Additional thread suggestions:

Satellite design/development/manufacture?

Deployment strategies/timelines/orbits?

Operations configurations/pricing/ground terminals?
Title: Re: Starlink : General Discussion - Thread 2
Post by: ninjaneer on 09/13/2019 06:13 pm
There will be a non-negligible number of people that jump onboard Starlink earlier than makes sense.  Personally if the price wasn't ridiculous I might pay just to be on the bleeding edge (for once, not my typical approach) BUT without going all-in meaning I'd have a backup unlimited connection.

Could you have Starlink end-user base stations able to leverage latent capacity on the user's backup connection to expand your effective base-station capacity?

Sort of seems shady but I find the notion intriguing.

Off my rocker?

I'm expecting to need geo overlap for about a year with traffic shaping and fallback.  There's going to be a lot of "oops" to work out.

Shaping takes a little skill but dual wan routers offering fallback aren't difficult to come by.
Title: Re: Starlink : General Discussion - Thread 2
Post by: AC in NC on 09/13/2019 06:20 pm
There will be a non-negligible number of people that jump onboard Starlink earlier than makes sense.  Personally if the price wasn't ridiculous I might pay just to be on the bleeding edge (for once, not my typical approach) BUT without going all-in meaning I'd have a backup unlimited connection.

Could you have Starlink end-user base stations able to leverage latent capacity on the user's backup connection to expand your effective base-station capacity?

Sort of seems shady but I find the notion intriguing.

Off my rocker?

I'm expecting to need geo overlap for about a year with traffic shaping and fallback.  There's going to be a lot of "oops" to work out.

Shaping takes a little skill but dual wan routers offering fallback aren't difficult to come by.

I reworded my question in the original post because it feels like I didn't communicate exactly what I was getting at:

Here's the reword:

Could you have Starlink end-user base stations able to have the Starlink equipment leverage the latent capacity on the user's alternate network connection in order to expand Starlink's effective base-station capacity?
Title: Re: Starlink : General Discussion - Thread 2
Post by: Lar on 09/13/2019 07:11 pm
How many places (in the target latitudes) are 300km in any direction from anything else? Customer ground stations can relay traffic that isn't the customer's... Xfinity uses this model to provide hotspots. So any other ship that has the service can relay for your ship.

I think the lack of laser links is a drawback but not the dealbreaker some think.
Title: Re: Starlink : General Discussion - Thread 2
Post by: ninjaneer on 09/13/2019 09:10 pm
I reworded my question in the original post because it feels like I didn't communicate exactly what I was getting at:

Here's the reword:

Could you have Starlink end-user base stations able to have the Starlink equipment leverage the latent capacity on the user's alternate network connection in order to expand Starlink's effective base-station capacity?

Yes.  That's just an internal dual WAN with one of the ports exposed as an external RJ45 with some traffic shaping rules applied.

In practice, though, that's a duct-taped feature that supports competitors' networks. Too much room for finger-pointing.  Advanced LAN/WAN features in ISP-provided routers tend to be poorly implemented without that kind of headache.  And a good gateway balancer like you are mentally picturing would cost more than the ISP modem itself.
Title: Re: Starlink : General Discussion - Thread 2
Post by: speedevil on 09/14/2019 12:09 am
How many places (in the target latitudes) are 300km in any direction from anything else? Customer ground stations can relay traffic that isn't the customer's... Xfinity uses this model to provide hotspots. So any other ship that has the service can relay for your ship.

I think the lack of laser links is a drawback but not the dealbreaker some think.
Where are you getting 300km from?
550km altitude, with a minimum service altitude for the sat at 15 degrees is ~1500km+ radius from the point on the earth below the satellite.
Or you can bounce to another customer station ~2000km away with no intersatellite links.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Nomadd on 09/14/2019 12:26 am
 Are sats in the same plane in sight of each other? If they were, it seems like it would be extremely easy for them to maintain constant rf links with their adjacent neighbors in the plane. They might not have the killer ping times, but it should be enough to cover the remote spots.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 09/14/2019 12:50 am
550km altitude, with a minimum service altitude for the sat at 15 degrees is ~1500km+ radius from the point on the earth below the satellite.
Or you can bounce to another customer station ~2000km away with no intersatellite links.

25 deg minimum angle during initial deployment, 40 degrees when more sats are up.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 09/14/2019 12:51 am
Are sats in the same plane in sight of each other? If they were, it seems like it would be extremely easy for them to maintain constant rf links with their adjacent neighbors in the plane. They might not have the killer ping times, but it should be enough to cover the remote spots.

They haven't applied to use RF links, and I don't think there's a ton of frequencies available.
Title: Re: Starlink : General Discussion - Thread 2
Post by: speedevil on 09/14/2019 12:54 am
550km altitude, with a minimum service altitude for the sat at 15 degrees is ~1500km+ radius from the point on the earth below the satellite.
Or you can bounce to another customer station ~2000km away with no intersatellite links.

25 deg minimum angle during initial deployment, 40 degrees when more sats are up.
Indeed, but much less than the ~70 degrees implied by 300km range.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Ludus on 09/14/2019 02:53 am
https://www.al.com/news/2019/09/can-elon-musks-spacex-bring-high-speed-internet-to-alabama.html (https://www.al.com/news/2019/09/can-elon-musks-spacex-bring-high-speed-internet-to-alabama.html)

This article estimates 250k-300k in rural Alabama with no wired internet access. I’m curious how that fit’s with estimates of the capacity of first generation Starlink to provide 25Mbps or better. AL is about 135k km^2.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Roy_H on 09/14/2019 05:43 am
I think the lack of laser links is a drawback but not the dealbreaker some think.

Do you know for a fact that the next Starlink launches don't have laser inter-satellite communication?
If Starlink has decided that laser communication is too difficult, wouldn't they fall back on microwave communication between sats instead of relying on ground stations?
Title: Re: Starlink : General Discussion - Thread 2
Post by: OTV Booster on 09/14/2019 01:26 pm
550km altitude, with a minimum service altitude for the sat at 15 degrees is ~1500km+ radius from the point on the earth below the satellite.
Or you can bounce to another customer station ~2000km away with no intersatellite links.

25 deg minimum angle during initial deployment, 40 degrees when more sats are up.


Where are the 15 and/or 25 deg numbers coming from?
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 09/14/2019 01:31 pm
25 deg minimum angle during initial deployment, 40 degrees when more sats are up.

Where are the 15 and/or 25 deg numbers coming from?

My numbers are from SpaceX's FCC filings.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 09/14/2019 01:52 pm
I think the lack of laser links is a drawback but not the dealbreaker some think.

Do you know for a fact that the next Starlink launches don't have laser inter-satellite communication?
If Starlink has decided that laser communication is too difficult, wouldn't they fall back on microwave communication between sats instead of relying on ground stations?

SpaceX has not applied for RF inter-satellite links, and that may be seen as a major change to the filing (which could have adverse affects when you're part of a processing round.)  There also aren't a lot of frequencies allocated for inter-satellite links.  There's a little bit in Ka-band, and then more in V band.

Just because a subsystem isn't ready yet that doesn't mean it needs to be jettisoned from the design.  They can make it work for now without them.  Oneweb's first generation doesn't have ISL either.
Title: Re: Starlink : General Discussion - Thread 2
Post by: OTV Booster on 09/14/2019 02:08 pm
Are sats in the same plane in sight of each other? If they were, it seems like it would be extremely easy for them to maintain constant rf links with their adjacent neighbors in the plane. They might not have the killer ping times, but it should be enough to cover the remote spots.

They haven't applied to use RF links, and I don't think there's a ton of frequencies available.

The problems go beyond licensing. Well, not problems but design issues. To make lateral coms work additional antennas are needed along with more bandwidth and power.  Any particular sat would be handling its ground customers with one system and an unknown amount of traffic on the lateral systems. Not a show stopper, just things to be dealt with.

As per RF vs laser... back in the day a laser running at 5% conversion efficiency was hot stuff. Don’t know where that stands now but the beam spread is small compared to any but the most elaborate (heavy, expensive) RF antennas. My gut says lasers might be a bit heavier but draw less power on the transmit side.

On the receive side I have no clue but (again gut) doubt it would mass much. No idea about power.

When we see fewer sats per launch or F9 expended, we’ll know something is up.

Phil

Edit: a reconsideration: a receive device for laser signal would have optics that could be heavy.

Title: Re: Starlink : General Discussion - Thread 2
Post by: Roy_H on 09/14/2019 04:26 pm
I think the lack of laser links is a drawback but not the dealbreaker some think.

Do you know for a fact that the next Starlink launches don't have laser inter-satellite communication?
If Starlink has decided that laser communication is too difficult, wouldn't they fall back on microwave communication between sats instead of relying on ground stations?

SpaceX has not applied for RF inter-satellite links, and that may be seen as a major change to the filing (which could have adverse affects when you're part of a processing round.)  There also aren't a lot of frequencies allocated for inter-satellite links.  There's a little bit in Ka-band, and then more in V band.

Just because a subsystem isn't ready yet that doesn't mean it needs to be jettisoned from the design.  They can make it work for now without them.  Oneweb's first generation doesn't have ISL either.

Whos jurisdiction is it that regulates inter-satellite communication? I would think it has to be international, like the regulation of geo sat slots. I also read somebody's post that there is no regulation, that all existing control only applies to earth links.
Title: Re: Starlink : General Discussion - Thread 2
Post by: speedevil on 09/14/2019 05:11 pm
Whos jurisdiction is it that regulates inter-satellite communication? I would think it has to be international, like the regulation of geo sat slots. I also read somebody's post that there is no regulation, that all existing control only applies to earth links.

For most plausible RF intersatelite links, unless they are at a frequency where the atmosphere is strongly absorbing, some will spill to the ground.
Title: Re: Starlink : General Discussion - Thread 2
Post by: OTV Booster on 09/14/2019 05:20 pm
I think the lack of laser links is a drawback but not the dealbreaker some think.

Do you know for a fact that the next Starlink launches don't have laser inter-satellite communication?
If Starlink has decided that laser communication is too difficult, wouldn't they fall back on microwave communication between sats instead of relying on ground stations?

SpaceX has not applied for RF inter-satellite links, and that may be seen as a major change to the filing (which could have adverse affects when you're part of a processing round.)  There also aren't a lot of frequencies allocated for inter-satellite links.  There's a little bit in Ka-band, and then more in V band.

Just because a subsystem isn't ready yet that doesn't mean it needs to be jettisoned from the design.  They can make it work for now without them.  Oneweb's first generation doesn't have ISL either.

Whos jurisdiction is it that regulates inter-satellite communication? I would think it has to be international, like the regulation of geo sat slots. I also read somebody's post that there is no regulation, that all existing control only applies to earth links.

The UN ITU has role but I don’t know exactly what it’s authorities are. As you said it works with GEO but don’t know how it works.

There was talk earlier in this thread, I think with accompanying FCC docs, concerning the different constellations interfering with each other and with GEO sats. IIRC the upshot was the providers need to work together to avoid problems. A constellation cross link could conceivably run on past the target and hit someone else’s sat.

If the ICU structures similar to the Outer Space Treaty authority ultimately devolves to the concerned States which in this case would be the FCC.

Phil
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 09/14/2019 07:18 pm
Whos jurisdiction is it that regulates inter-satellite communication? I would think it has to be international, like the regulation of geo sat slots. I also read somebody's post that there is no regulation, that all existing control only applies to earth links.

The FCC regulates RF inter-satellite links for US registered satellites.  The international and US frequency tables have certain bands where ISL are allowed.  If you read someone saying they're not regulated, then that person is totally clueless and you should not pay attention to anything they say about the subject.
Title: Re: Starlink : General Discussion - Thread 2
Post by: dondar on 09/14/2019 09:51 pm
Whos jurisdiction is it that regulates inter-satellite communication? I would think it has to be international, like the regulation of geo sat slots. I also read somebody's post that there is no regulation, that all existing control only applies to earth links.

The FCC regulates RF inter-satellite links for US registered satellites.  The international and US frequency tables have certain bands where ISL are allowed.  If you read someone saying they're not regulated, then that person is totally clueless and you should not pay attention to anything they say about the subject.
SpaceX intends to use laser inter-satellite links.
 use of the frequencies above 3000GHz is not regulated.
Since the open positions of the optical manufacturing team are all removed in the second half of august I would expect that the team is full. It means that SpaceX should come with proper "initial"prototype in the next 2-4 months.
There are no specific strange requirements beside easily destructible mirror. the problem they have allegedly solved months ago. Hence a couple of months instead of years.

I remind typical "feature" of SpaceX requirements, not surprisingly repeated in all optic positions.
Quote
ADDITIONAL REQUIREMENTS:

    Extended hours and weekend work, as needed, in support of critical milestones and operational needs
p.s. I will make an exception (I have no habit to make complete ready to copypast posts because of pesky students ready to copy everything and everywhere) and  will drop direct quote from the relevant regulation:
Quote
7.1.1LASERS AND OTHER SYSTEMS THAT OPERATE ABOVE 3000 GHz

No authorization is required for the use of frequencies above 3000 GHz.

As a matter of information, agencies may inform the IRAC of such usage, but no record of it shall be kept in the Government Master File (GMF), the list of Frequency Assignments to Government RadioStations.

NTIA has the authority under the Communications Act of 1934, as amended, to license stations that operate above 3000 GHz, including lasers, but at this time does not choose to do so.
For those who have never heard about NTIA.
Here is relevant and very concise explanation:
https://www.ntia.doc.gov/legacy/osmhome/roosa4.html
Title: Re: Starlink : General Discussion - Thread 2
Post by: Semmel on 09/14/2019 11:14 pm
SpaceX intends to use laser inter-satellite links.
 use of the frequencies above 3000GHz is not regulated.
Since the open positions of the optical manufacturing team are all removed in the second half of august I would expect that the team is full. It means that SpaceX should come with proper "initial"prototype in the next 2-4 months.
There are no specific strange requirements beside easily destructible mirror. the problem they have allegedly solved months ago. Hence a couple of months instead of years.

I bet the problem is not regulation or mirror production, but laser pointing. They know where each satellite is, so an open loop pointing model would be sufficient, but maybe its hard if the beam is very narrow.

The alternative would be to use very large beams that dont require steering, but then they might illuminate multiple sats with the same beam which is a tricky interference problem. A sparsely populated orbital plane would help because it would increase the angular distance between two consecutive sats in the same plane. Maybe push the further away sat over the horizon. This would make the problem much easier.

Maybe thats behind the change in plane population that SpaceX filed with the FAA?

Lets do the math. Say we want to compute the minimal hight over earth of the direct line between one set and the second next sat. The sats are at 500km, or at about 7000 km from the center of earth. So the height over ground of the connecting line between sat 1 and sat 3 in an orbital plane is:
h = (6500 + 500) * cos (360 / 66) - 6500 = 450 km. (roughly)

Lets take the new proposal of 22 sats per plane. Then the height changes to
h = (6500 + 500) * cos (360 / 22) - 6500 = 216 km. (roughly)

So the sat will still see the second further satellite. Maybe they can deal with the interference from one satellite but not from two? But whats the angle? By geometry, the angle between one satellite line of sight and the next satellite is equal to the angle between their location in the orbital plane and the center of earth. In the first proposal, the sat to sat angular distance is 5.45 degrees. In the second proposal 16.4. Maybe they can make the satellite connection beams with a solid cone of about 20 degrees opening angle, then they would illuminate only one of them, but would have room for manoeuvring of about 10 (or with margin 5) degrees. That sounds realistic.

So a sparcely populated orbital plane would gain them that they dont need steerable beams, if they can keep each satellite within 5 degrees in all angles.

I have no idea how that would work for links to neighbouring planes though. maybe they do need steerable mirrors for these after all. But that problem also becomes much easier with a wider beam.
Title: Re: Starlink : General Discussion - Thread 2
Post by: OTV Booster on 09/15/2019 01:35 am
SpaceX intends to use laser inter-satellite links.
 use of the frequencies above 3000GHz is not regulated.
Since the open positions of the optical manufacturing team are all removed in the second half of august I would expect that the team is full. It means that SpaceX should come with proper "initial"prototype in the next 2-4 months.
There are no specific strange requirements beside easily destructible mirror. the problem they have allegedly solved months ago. Hence a couple of months instead of years.

I bet the problem is not regulation or mirror production, but laser pointing. They know where each satellite is, so an open loop pointing model would be sufficient, but maybe its hard if the beam is very narrow.

The alternative would be to use very large beams that dont require steering, but then they might illuminate multiple sats with the same beam which is a tricky interference problem. A sparsely populated orbital plane would help because it would increase the angular distance between two consecutive sats in the same plane. Maybe push the further away sat over the horizon. This would make the problem much easier.

Maybe thats behind the change in plane population that SpaceX filed with the FAA?

Lets do the math. Say we want to compute the minimal hight over earth of the direct line between one set and the second next sat. The sats are at 500km, or at about 7000 km from the center of earth. So the height over ground of the connecting line between sat 1 and sat 3 in an orbital plane is:
h = (6500 + 500) * cos (360 / 66) - 6500 = 450 km. (roughly)

Lets take the new proposal of 22 sats per plane. Then the height changes to
h = (6500 + 500) * cos (360 / 22) - 6500 = 216 km. (roughly)

So the sat will still see the second further satellite. Maybe they can deal with the interference from one satellite but not from two? But whats the angle? By geometry, the angle between one satellite line of sight and the next satellite is equal to the angle between their location in the orbital plane and the center of earth. In the first proposal, the sat to sat angular distance is 5.45 degrees. In the second proposal 16.4. Maybe they can make the satellite connection beams with a solid cone of about 20 degrees opening angle, then they would illuminate only one of them, but would have room for manoeuvring of about 10 (or with margin 5) degrees. That sounds realistic.

So a sparcely populated orbital plane would gain them that they dont need steerable beams, if they can keep each satellite within 5 degrees in all angles.

I have no idea how that would work for links to neighbouring planes though. maybe they do need steerable mirrors for these after all. But that problem also becomes much easier with a wider beam.

Does it make sense for laser output to illuminate the interior of a diffuser of spherical section that can be seen from a wide angle? The power requirements go up but steering would become a non issue. One laser could transmit to any and all sats over a wide angular range with a simple header doing something like MAC addressing for the intended recipient sat. Broadcast instead of P2P.

Indeed, would it need to be a laser? Does lasing enable the fast switching needed for high speed digital encoding or is this something that can be designed into a non lasing LED?

Phil
Title: Re: Starlink : General Discussion - Thread 2
Post by: Nomadd on 09/15/2019 01:59 am
SpaceX intends to use laser inter-satellite links.
 use of the frequencies above 3000GHz is not regulated.
Since the open positions of the optical manufacturing team are all removed in the second half of august I would expect that the team is full. It means that SpaceX should come with proper "initial"prototype in the next 2-4 months.
There are no specific strange requirements beside easily destructible mirror. the problem they have allegedly solved months ago. Hence a couple of months instead of years.

I bet the problem is not regulation or mirror production, but laser pointing. They know where each satellite is, so an open loop pointing model would be sufficient, but maybe its hard if the beam is very narrow.

The alternative would be to use very large beams that dont require steering, but then they might illuminate multiple sats with the same beam which is a tricky interference problem. A sparsely populated orbital plane would help because it would increase the angular distance between two consecutive sats in the same plane. Maybe push the further away sat over the horizon. This would make the problem much easier.

Maybe thats behind the change in plane population that SpaceX filed with the FAA?

Lets do the math. Say we want to compute the minimal hight over earth of the direct line between one set and the second next sat. The sats are at 500km, or at about 7000 km from the center of earth. So the height over ground of the connecting line between sat 1 and sat 3 in an orbital plane is:
h = (6500 + 500) * cos (360 / 66) - 6500 = 450 km. (roughly)

Lets take the new proposal of 22 sats per plane. Then the height changes to
h = (6500 + 500) * cos (360 / 22) - 6500 = 216 km. (roughly)

So the sat will still see the second further satellite. Maybe they can deal with the interference from one satellite but not from two? But whats the angle? By geometry, the angle between one satellite line of sight and the next satellite is equal to the angle between their location in the orbital plane and the center of earth. In the first proposal, the sat to sat angular distance is 5.45 degrees. In the second proposal 16.4. Maybe they can make the satellite connection beams with a solid cone of about 20 degrees opening angle, then they would illuminate only one of them, but would have room for manoeuvring of about 10 (or with margin 5) degrees. That sounds realistic.

So a sparcely populated orbital plane would gain them that they dont need steerable beams, if they can keep each satellite within 5 degrees in all angles.

I have no idea how that would work for links to neighbouring planes though. maybe they do need steerable mirrors for these after all. But that problem also becomes much easier with a wider beam.
That would take a laser comms guy to figure. I've seen high frequency microwave signals pulled out of a rats nest of rf very close frequency wise and 40db hotter than the desired signal. I'm not sure how selective laser channels can be.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Barley on 09/15/2019 03:53 am
So a sparcely populated orbital plane would gain them that they dont need steerable beams, if they can keep each satellite within 5 degrees in all angles.
Don't you need a steerable beam so you can point the solar panel (roughly) at the sun and the antenna (roughly) at the earth?
Title: Re: Starlink : General Discussion - Thread 2
Post by: Comga on 09/15/2019 05:07 am
Does it make sense for laser output to illuminate the interior of a diffuser of spherical section that can be seen from a wide angle? The power requirements go up but steering would become a non issue. One laser could transmit to any and all sats over a wide angular range with a simple header doing something like MAC addressing for the intended recipient sat. Broadcast instead of P2P.

Indeed, would it need to be a laser? Does lasing enable the fast switching needed for high speed digital encoding or is this something that can be designed into a non lasing LED?

Phil
No it does not make sense
Yes it has to be a laser
Power requirements going up is very bad
There is no need to worry about seeing a laser link from beyond the nearest one. R squared and pointing will prevent that.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Semmel on 09/15/2019 08:23 am
That would take a laser comms guy to figure. I've seen high frequency microwave signals pulled out of a rats nest of rf very close frequency wise and 40db hotter than the desired signal. I'm not sure how selective laser channels can be.

You can do that of course if you know what you are looking for. But the laser links are high bandwidth low latency. No fancy post processing (takes time) and as small interference as possible (bandwidth). Also you want to have the sun in your receiver, so that has to be pointing too. Assuming they use the same telescope for emitting and receiving with a beam splitter, the receiving cone would be the same as the emitting cone. So too wide angle might be counter productive.
Title: Re: Starlink : General Discussion - Thread 2
Post by: dondar on 09/15/2019 08:48 am
SpaceX intends to use laser inter-satellite links.
 use of the frequencies above 3000GHz is not regulated.
Since the open positions of the optical manufacturing team are all removed in the second half of august I would expect that the team is full. It means that SpaceX should come with proper "initial"prototype in the next 2-4 months.
There are no specific strange requirements beside easily destructible mirror. the problem they have allegedly solved months ago. Hence a couple of months instead of years.

I bet the problem is not regulation or mirror production, but laser pointing. They know where each satellite is, so an open loop pointing model would be sufficient, but maybe its hard if the beam is very narrow.

The alternative would be to use very large beams that dont require steering, but then they might illuminate multiple sats with the same beam which is a tricky interference problem. A sparsely populated orbital plane would help because it would increase the angular distance between two consecutive sats in the same plane. Maybe push the further away sat over the horizon. This would make the problem much easier.

Maybe thats behind the change in plane population that SpaceX filed with the FAA?

Lets do the math. Say we want to compute the minimal hight over earth of the direct line between one set and the second next sat. The sats are at 500km, or at about 7000 km from the center of earth. So the height over ground of the connecting line between sat 1 and sat 3 in an orbital plane is:
h = (6500 + 500) * cos (360 / 66) - 6500 = 450 km. (roughly)

Lets take the new proposal of 22 sats per plane. Then the height changes to
h = (6500 + 500) * cos (360 / 22) - 6500 = 216 km. (roughly)

So the sat will still see the second further satellite. Maybe they can deal with the interference from one satellite but not from two? But whats the angle? By geometry, the angle between one satellite line of sight and the next satellite is equal to the angle between their location in the orbital plane and the center of earth. In the first proposal, the sat to sat angular distance is 5.45 degrees. In the second proposal 16.4. Maybe they can make the satellite connection beams with a solid cone of about 20 degrees opening angle, then they would illuminate only one of them, but would have room for manoeuvring of about 10 (or with margin 5) degrees. That sounds realistic.

So a sparcely populated orbital plane would gain them that they dont need steerable beams, if they can keep each satellite within 5 degrees in all angles.

I have no idea how that would work for links to neighbouring planes though. maybe they do need steerable mirrors for these after all. But that problem also becomes much easier with a wider beam.
1. I believe SpaceX  intended to use initially out of shelf laser comm links.  the problem was that  all existing solutions use hard mirrors which do not want to burn in atmosphere. This was the core of the first  sh&t storm wave "Starlink is bAAAd". Since they have got ideas about how to fix it they moved all "in-house" and started to develop their own solution.
2. Beams forming and steering is done by mirrors. There is no problem to make steerable solutions. It is routine work.  Unlike RF this can be done in fine flexible and compact manner.
Detectors can (and usually do) use steerable mirrors either. Interference is "weak" problem.
Mechanical optical scanners using steerable mirrors are old as a modern astronomy is.

3. Starlink pizzas have amazing power ration. The sail they have is huge. Power is not an issue either.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Comga on 09/15/2019 02:34 pm
Yes. It takes a lasercomm engineer
(I am not a lasercomm engineer but am qualified to be one if the opportunity arose.)
Bandwidths are not like microwaves. Communication is rarely coherent but it could be.  But there is an enormous amount of bandwidth in that sense.
There is little fear of crosstalk
Power is always an issue
Lasercomm can be made nearly insensitive to solar blinding.
A project I was on once successfully pointed at a moving satellite and a ground station but it wasn’t simple. That level of beam steering is very difficult, and would be needed for links between planes
Starlink can buy lasercomm links, just not at a price that works for constellations of thousands of satellites.
SpaceX bought lidar systems for the first few Dragon flights, then made their own.
We will see what Starlink can come up with
Title: Re: Starlink : General Discussion - Thread 2
Post by: Semmel on 09/15/2019 07:01 pm
You convinced me that steering and pointing is not the most difficult problem. So far, we did not come up with any very difficult problem. However, we DO know that the intersat links have problems, otherwise they would not be on the critical path for Starlink and the first batch of sats would have had them. So there must be something that is hard/difficult/nonobvious that we miss.
Title: Re: Starlink : General Discussion - Thread 2
Post by: speedevil on 09/15/2019 08:59 pm
You convinced me that steering and pointing is not the most difficult problem. So far, we did not come up with any very difficult problem. However, we DO know that the intersat links have problems, otherwise they would not be on the critical path for Starlink and the first batch of sats would have had them. So there must be something that is hard/difficult/nonobvious that we miss.

An isolated starlink, floating in space, pointing at one distant target is a moderately easier problem than one using at least two links talking to satellites at relatively rapidly changing range and angle, with the requirement to be able to switch rapidly between targets and lock fast.
Title: Re: Starlink : General Discussion - Thread 2
Post by: AC in NC on 09/15/2019 09:03 pm
So there must be something that is hard/difficult/nonobvious that we miss.

Forgive me if I missed a now-dismissed concern but I vaguely recollected that one factor for ISL was affordable optics.  Combined with other challenges it could mushroom.  IDK.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Roy_H on 09/15/2019 10:49 pm
So from the above posts, it seems that if Starlink uses RF ISL then we would know about it due to licencing requirements but not if they are using lasers. Wide beam lasers would require significantly extra power and I think unlikely. Precision aiming and tracking would certainly be a major challenge but not insurmountable. So I believe it remains at least plausible if not likely that the next Starlink launch has satellites with laser ISL.
Title: Re: Starlink : General Discussion - Thread 2
Post by: OTV Booster on 09/15/2019 11:15 pm
I know SX likes commonality but might it make sense for the ‘final’ rollout to have two different types? Lower orbits more densely packed with direct customer connection and in the higher orbit sats that do only cross connect and high bandwidth downlink to data centers to hit copper. The customer connect sats would have lateral coms only to the high sats.

Just thinking out loud.

Phil
Title: Re: Starlink : General Discussion - Thread 2
Post by: Barley on 09/16/2019 05:09 am
An isolated starlink, floating in space, pointing at one distant target is a moderately easier problem than one using at least two links talking to satellites at relatively rapidly changing range and angle, with the requirement to be able to switch rapidly between targets and lock fast.

I may be visualizing this incorrectly but it seems that neighboring satellites in the same plane are at a constant distances and slowly changing bearing; while neighboring satellites in adjacent planes are at a very slowly changing bearing and slowly changing distance.

You could have a useful net without dealing with rapid changes, re-targeting or needing a fast lock.  It would need multiple links per satellite, but that can be done by replicating the optical hardware.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Comga on 09/16/2019 05:58 am
You convinced me that steering and pointing is not the most difficult problem. So far, we did not come up with any very difficult problem. However, we DO know that the intersat links have problems, otherwise they would not be on the critical path for Starlink and the first batch of sats would have had them. So there must be something that is hard/difficult/nonobvious that we miss.

If you mean that I convinced you, that would indicate a failure on my part.
Pointing may not be THE most difficult problem, but it is a real tough problem, with serious mass, power, and cost implications.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Semmel on 09/16/2019 11:35 am
You convinced me that steering and pointing is not the most difficult problem. So far, we did not come up with any very difficult problem. However, we DO know that the intersat links have problems, otherwise they would not be on the critical path for Starlink and the first batch of sats would have had them. So there must be something that is hard/difficult/nonobvious that we miss.

If you mean that I convinced you, that would indicate a failure on my part.
Pointing may not be THE most difficult problem, but it is a real tough problem, with serious mass, power, and cost implications.

dondar mentioned beam steering is done routinely. I guess he knows more about it than I do, so I tend to believe him.

Lets break it down how I would do the implementation. The optical layout would be something like this:

Emitter and Receiver are mounted at 90 deg to each other with a beam splitter in between. The beam splitter is 50/50, such that half the emitter beam is going through to the exit and half if it is lost. The same happens to the receiver beam in reverse, where half the light goes straight through to the emitter and is lost and the other half is going to the receiver. After the beam splitter comes a beam splitter and a small, commercial telescope with an exit that goes to the steerable mirror solution in tip/tilt.

This arrangement looses 75% of the light, but has the advantage that the receiver can be used to steer the emitting beam. You could make the receiving and emitting wavelength different and use a di-chroic instead of a beam splitter, but then there would be 2 types of intersat receiver/emitter pair and you would need to pair them up like a male/female connector. Possible if the orientation of all sats remain the same and emit green forward and right and red backwards and left, for instance. Then you would not loose the 75% of light at the expense of less flexibility.

In front of the receiver is a 45 deg mirror with a hole in the middle. Whenever the telescope is not pointed directly at the emitter satellite, the light would leave the whole and be detected by the camera, which then can correct the steering of the mirror at the exit. Both reciever and emitter could be optical fibres to guide the light to some other location in the satellite.

I would be happy for comments and where people see things that are difficult.
Title: Re: Starlink : General Discussion - Thread 2
Post by: guckyfan on 09/16/2019 01:51 pm
@Semmel

Just a question from ignorance. Why would the transmitted laser signal need to go through the telescope mirror? Isn't the laser beam as parallel as it can be? I imagined two separate signal channels for transmit and receive, except for the steerable mirror. The telescope only increases the amount of received signal.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Lar on 09/16/2019 02:19 pm
550km altitude, with a minimum service altitude for the sat at 15 degrees is ~1500km+ radius from the point on the earth below the satellite.
Or you can bounce to another customer station ~2000km away with no intersatellite links.

25 deg minimum angle during initial deployment, 40 degrees when more sats are up.
Indeed, but much less than the ~70 degrees implied by 300km range.
300km was a worst case number. The actual range is farther, to be sure.

(as to where I got the number, somewhere behind me, not too far away, and a bit lower than my head...)

I think the lack of laser links is a drawback but not the dealbreaker some think.

Do you know for a fact that the next Starlink launches don't have laser inter-satellite communication?
If Starlink has decided that laser communication is too difficult, wouldn't they fall back on microwave communication between sats instead of relying on ground stations?
I don't think they decided this. Just that maybe the initial set might not have it.... Just guessing that they might not and thinking about how to work around it.. If they do, this is a moot point I guess.

(As others say, there might not be a lot of available bandwidth for intersat microwave linkw)
Title: Re: Starlink : General Discussion - Thread 2
Post by: Semmel on 09/16/2019 02:44 pm
@Semmel

Just a question from ignorance. Why would the transmitted laser signal need to go through the telescope mirror? Isn't the laser beam as parallel as it can be? I imagined two separate signal channels for transmit and receive, except for the steerable mirror. The telescope only increases the amount of received signal.

You are right, a laser is quite focused, with only a few degrees of opening angle. The idea behind the design I propose is to steer the laser using the focal plane of the receiver.
An other idea would be to use a Schmidt-Cassegrain telescope and pick up the emitter laser with a mirror in the central obstruction of the telescope. During manufacturing you make sure it is pointing reasonably parallel with the telescope beam. This gets away with the 75% reduction in illumination due to the beam splitter and is a better design. Thx. I made an alternative drawing.
Title: Re: Starlink : General Discussion - Thread 2
Post by: philw1776 on 09/16/2019 03:51 pm
SpaceX intends to use laser inter-satellite links.
 use of the frequencies above 3000GHz is not regulated.
Since the open positions of the optical manufacturing team are all removed in the second half of august I would expect that the team is full. It means that SpaceX should come with proper "initial"prototype in the next 2-4 months.
There are no specific strange requirements beside easily destructible mirror. the problem they have allegedly solved months ago. Hence a couple of months instead of years.

I bet the problem is not regulation or mirror production, but laser pointing. They know where each satellite is, so an open loop pointing model would be sufficient, but maybe its hard if the beam is very narrow.

The alternative would be to use very large beams that dont require steering, but then they might illuminate multiple sats with the same beam which is a tricky interference problem. A sparsely populated orbital plane would help because it would increase the angular distance between two consecutive sats in the same plane. Maybe push the further away sat over the horizon. This would make the problem much easier.

Maybe thats behind the change in plane population that SpaceX filed with the FAA?

Lets do the math. Say we want to compute the minimal hight over earth of the direct line between one set and the second next sat. The sats are at 500km, or at about 7000 km from the center of earth. So the height over ground of the connecting line between sat 1 and sat 3 in an orbital plane is:
h = (6500 + 500) * cos (360 / 66) - 6500 = 450 km. (roughly)

Lets take the new proposal of 22 sats per plane. Then the height changes to
h = (6500 + 500) * cos (360 / 22) - 6500 = 216 km. (roughly)

So the sat will still see the second further satellite. Maybe they can deal with the interference from one satellite but not from two? But whats the angle? By geometry, the angle between one satellite line of sight and the next satellite is equal to the angle between their location in the orbital plane and the center of earth. In the first proposal, the sat to sat angular distance is 5.45 degrees. In the second proposal 16.4. Maybe they can make the satellite connection beams with a solid cone of about 20 degrees opening angle, then they would illuminate only one of them, but would have room for manoeuvring of about 10 (or with margin 5) degrees. That sounds realistic.

So a sparcely populated orbital plane would gain them that they dont need steerable beams, if they can keep each satellite within 5 degrees in all angles.

I have no idea how that would work for links to neighbouring planes though. maybe they do need steerable mirrors for these after all. But that problem also becomes much easier with a wider beam.
That would take a laser comms guy to figure. I've seen high frequency microwave signals pulled out of a rats nest of rf very close frequency wise and 40db hotter than the desired signal. I'm not sure how selective laser channels can be.

Perhaps use of WDM where certain clusters of sats use certain wavelengths.  Can also be varied over time.
Title: Re: Starlink : General Discussion - Thread 2
Post by: oldAtlas_Eguy on 09/16/2019 04:02 pm
@Semmel

Just a question from ignorance. Why would the transmitted laser signal need to go through the telescope mirror? Isn't the laser beam as parallel as it can be? I imagined two separate signal channels for transmit and receive, except for the steerable mirror. The telescope only increases the amount of received signal.

You are right, a laser is quite focused, with only a few degrees of opening angle. The idea behind the design I propose is to steer the laser using the focal plane of the receiver.
An other idea would be to use a Schmidt-Cassegrain telescope and pick up the emitter laser with a mirror in the central obstruction of the telescope. During manufacturing you make sure it is pointing reasonably parallel with the telescope beam. This gets away with the 75% reduction in illumination due to the beam splitter and is a better design. Thx. I made an alternative drawing.
To answer the question of multi frequency operation use a diffraction grating for narrow band filter and the result is a line of dots representing the different frequencies. Also not using the ones associated with higher outputs of the sun enables operation at very close angles to the sun without ever burning out a detector.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Barley on 09/16/2019 04:18 pm

This arrangement looses 75% of the light, but has the advantage that the receiver can be used to steer the emitting beam. You could make the receiving and emitting wavelength different and use a di-chroic instead of a beam splitter, but then there would be 2 types of intersat receiver/emitter pair and you would need to pair them up like a male/female connector. Possible if the orientation of all sats remain the same and emit green forward and right and red backwards and left, for instance. Then you would not loose the 75% of light at the expense of less flexibility.

The solar array has one axis of motion.  Tracking the other axis requires the satellite to rotate around the local vertical..  This means a 360 degree rotation per year.  So four times a year you would have to rotate the entire array.  Green forward & right -> green left & forward -> green back & left -> green right & back.

Rotating a single satellite 90 degrees leaves it with two working links, so you would not have to rotate the entire array instantly.   Rotating a few at a time over the Pacific for example.  Still it would add some interesting operational constraints.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gdelottle on 09/16/2019 04:27 pm
@Semmel
You are right, a laser is quite focused, with only a few degrees of opening angle. The idea behind the design I propose is to steer the laser using the focal plane of the receiver.

Actually a few microrad beam width, not degrees, are achievable.
Title: Re: Starlink : General Discussion - Thread 2
Post by: eriblo on 09/16/2019 05:10 pm
@Semmel

Just a question from ignorance. Why would the transmitted laser signal need to go through the telescope mirror? Isn't the laser beam as parallel as it can be? I imagined two separate signal channels for transmit and receive, except for the steerable mirror. The telescope only increases the amount of received signal.
Even an ideal monochrome laser (which would be useless) is diffraction limited by its emitting aperture like all other EM radiation, with the telescope having the same function as radio antenna with its associated gain. Apart from technological limitations it does not matter if you use it to increase the signal on the receiving end or the transmitting end with the ideal situation being to use the same hardware for both.
Title: Re: Starlink : General Discussion - Thread 2
Post by: CuddlyRocket on 09/16/2019 06:00 pm
The alternative would be to use very large beams that dont require steering, but then they might illuminate multiple sats with the same beam which is a tricky interference problem.

You probably want to minimise the chances of illuminating satellites that are not part of the Starlink constellation. Also illuminating targets on the ground.

There's probably no real problem, but people can get really upset if they think there is - see the recent bout of outrage from parts of the astronimical community - and foreign governments can be even less rational!
Title: Re: Starlink : General Discussion - Thread 2
Post by: OTV Booster on 09/16/2019 06:18 pm
There is a tension between a tight beam to keep the signal concentrated and a wide beam to reduce targeting precision. As usual the trade off will be somewhere between he extremes. But we need numbers to even begin looking at the trades. So here are a few things that might be on point.

- what is the narrowest beam that is economically realistic. What wavelength, output and conversion efficiency? That will cover a range of options but maybe set some limits.

- on the receiving end I’d guess CCD but only guessing. Again guessing, the array need only be big enough to fill the focal plane of the unknown optics but sensitivity is important. Optimize for one wavelength or multiplex several. Use polarization for encoding?

- dB loss over the expected distances.

- Cryo can radically boost CCD sensitivity. Coolant & system mass vs bigger array & battery mass. Would it survive reentry?

The more I think about this the bigger the trade space gets. There are at least a dozen other things my amateur astronomy dweebishness bring to mind. Probably why SX is putting it off.

Phil
Title: Re: Starlink : General Discussion - Thread 2
Post by: Semmel on 09/16/2019 07:12 pm
The beamwidth of the laser for satlinks is a funktion of the pointing accuracy of the steerable mirror. You want your laser beam cone to be larger than the pointing error. So a too narrow laser beam might be counterproductive. At the same time, you want the beam as narrow as possible to reduce the power requirements.

Come to think of it, optical com systems are not superbright. Maybe they can't buy the laser off the shelf and developing modulation hardware for a more powerful system is probably not easy. I have no idea how that is done anyway, comga, can you comment?
Title: Re: Starlink : General Discussion - Thread 2
Post by: thirtyone on 09/16/2019 07:51 pm
To give you guys an idea of general feasibility, here's another company which seems to be offering a completed module for space laser communications systems (http://www.spacemicro.com/assets/datasheets/rf-and-microwave/lasercom.pdf). In summary, they claim 4,750km max range for an LEO cross-link at 51W for 10Gbps at 7.5kg, to 240W for 100Gbps at 26kg. These options seem well within the mass/power requirements of Starlink, if they are to be believed.

The company seems to be well established, and that module datasheet gives you a sense of power and size required to communicate as a cross-link in LEO.

There is also an entire panel on laser satellite communications in an industry conference on "directed energy": https://www.boozallen.com/d/multimedia/2019-directed-energy-summit-video-highlights.html (https://www.boozallen.com/d/multimedia/2019-directed-energy-summit-video-highlights.html)

Here's an article on optical comsats, with an intriguing quote from the CEO of Space Micro, who mentions that their space laser system will be in orbit "later this year." I wonder if they are actually quietly a supplier for perhaps the first generation of SpaceX satellites (I know SpaceX likes doing things in-house, but perhaps this was a feasibility study). Or maybe one of their competitors testing a similar system. Or some HFT trading company using it for some latency shenanigans.

https://breakingdefense.com/2019/03/say-it-with-space-lasers-optical-comsats-for-major-war/ (https://breakingdefense.com/2019/03/say-it-with-space-lasers-optical-comsats-for-major-war/)

Here's the wikipedia on laser communications in space. Looks like the ESA already has a functional laser communications system that can communicate between LEO and GEO. My impression is that because there is no atmosphere, sat-sat communications is considerably simpler despite the high relative velocities. The first successful sat-sat optical link was achieved as early as 2008:
https://www.dlr.de/en/desktopdefault.aspx/tabid-78/7420_read-14120/ (https://www.dlr.de/en/desktopdefault.aspx/tabid-78/7420_read-14120/)
Title: Re: Starlink : General Discussion - Thread 2
Post by: oldAtlas_Eguy on 09/16/2019 07:56 pm
At a minimum the total bandwidth of the ISlink should be equal to that of the to ground total bandwidth of the sat. But it would be better if it was at 2X.
This implies that the devices will be multi-spectral with multiple different color lasers and detectors on a single telescope/device.

It has never been the electronic side that has been the challenge but the optical materials. Based on the optical gain/loss values for particular material it drives primarily the laser output power requirement. Laser output points power then sets thermal requirements. Size is already set because it mustfit in the sat flatpack. There is a ~30cm thickness allowing for a posible 20cm diameter telescope and a aimable mirror that can give a 90 degree field of view aiming on 2 axis (the mirror is retangular in shape to make it able to move +-45 in one axis and 30/60 in the other.
Title: Re: Starlink : General Discussion - Thread 2
Post by: thirtyone on 09/16/2019 08:21 pm
Another interesting technical comparison, done by a group with more experience with satellites/communications:

http://www.mit.edu/~portillo/files/Comparison-LEO-IAC-2018-slides.pdf

Telesat is a much more mature satellite company, so I think there's not nearly as much PR around them. But based on this particular group's estimations, it looks like they may be a more serious competitor, at least in terms of total bandwidth, than OneWeb, which is almost a bit of a joke given these estimations.

I actually on ran into these slides while looking at Telesat's lasercom ISLs.

I am not experienced enough and have not spent more time looking through the author's assumptions, though, so I encourage others to take a look at those slides. So many things change with these systems so often that the conclusions may no longer be valid.

edit:
Here's the paper that came out of that conference:
http://systemarchitect.mit.edu/docs/delportillo19a.pdf

edit2:
and some quotes from the conclusion:
Quote
The maximum total system throughput (sellable capacity) for OneWeb’s, Telesat’s and SpaceX’s constellations are 1.56 Tbps, 2.66 Tbps and 23.7 Tbps respectively.
Quote
A ground segment comprising of 42 ground stations will suffice to handle all of Telesat’s capacity, whereas OneWeb will need at least 71 ground stations, and SpaceX more than 123.
Quote
OneWeb’s system has a lower throughput than Telesat’s, even though the number of satellites in the former is significantly larger. The main reason for this are the lower data-rate per satellite that results from OneWeb’s low-complexity satellite design, spectrum utilization strategy, orbital configuration, and payload design, as well as the lack of use of ISLs.
And a bit more on-topic, there's a great plot of the estimated total system bandwidth of SpaceX's constellation on page 12 with and without ISL. Starlink has the most to gain from ISL in part due to the huge number of ground stations required for good efficiency. Even so, OneWeb's system design is such that even with ISLs on OneWeb (which it is not planning on) and no ISLs on Starlink, OneWeb will still have less system throughput. Telesat seems to have the most "efficient" system by far (neglecting complexity, launch cadence, etc.), possibly because they're the most conservative with things like how many ground stations they can expect to operate, how many satellites they can launch, experience with building fewer, heavier satellites, etc.
Title: Re: Starlink : General Discussion - Thread 2
Post by: ncb1397 on 09/16/2019 08:40 pm

Telesat is a much more mature satellite company, so I think there's not nearly as much PR around them. But based on this particular group's estimations, it looks like they may be a more serious competitor, at least in terms of total bandwidth, than OneWeb, which is almost a bit of a joke given these estimations.

The paper estimates OneWeb's throughput at 15 megabits per kilogram while they estimate SpaceX's throughput at 13.9 megabits per kilogram.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Semmel on 09/16/2019 08:56 pm
Thx for this trove of data, will look at it in daylight tomorrow.!
Title: Re: Starlink : General Discussion - Thread 2
Post by: envy887 on 09/16/2019 09:02 pm

Telesat is a much more mature satellite company, so I think there's not nearly as much PR around them. But based on this particular group's estimations, it looks like they may be a more serious competitor, at least in terms of total bandwidth, than OneWeb, which is almost a bit of a joke given these estimations.

The paper estimates OneWeb's throughput at 15 megabits per kilogram while they estimate SpaceX's throughput at 13.9 megabits per kilogram.

The v0.9 launch had 227 kg satellites, not 386 kg as noted there. That bumps the Mb/kg to over 20.

Unless you want to posit that F9 can lift .386*60 = 23.2 t to 440 km circular LEO and still stick a barge landing?
Title: Re: Starlink : General Discussion - Thread 2
Post by: ncb1397 on 09/16/2019 09:12 pm

Telesat is a much more mature satellite company, so I think there's not nearly as much PR around them. But based on this particular group's estimations, it looks like they may be a more serious competitor, at least in terms of total bandwidth, than OneWeb, which is almost a bit of a joke given these estimations.

The paper estimates OneWeb's throughput at 15 megabits per kilogram while they estimate SpaceX's throughput at 13.9 megabits per kilogram.

The v0.9 launch had 227 kg satellites, not 386 kg as noted there. That bumps the Mb/kg to over 20.

Unless you want to posit that F9 can lift .386*60 = 23.2 t to 440 km circular LEO and still stick a barge landing?

The v0.9 satellites don't have intersatellite links. The estimated throughput in that case in the paper is about 10 terabits per second. Using 227 kg and 10 terabits per second is even worse at 10 megabits per kilogram.
Title: Re: Starlink : General Discussion - Thread 2
Post by: thirtyone on 09/16/2019 09:12 pm

Telesat is a much more mature satellite company, so I think there's not nearly as much PR around them. But based on this particular group's estimations, it looks like they may be a more serious competitor, at least in terms of total bandwidth, than OneWeb, which is almost a bit of a joke given these estimations.

The paper estimates OneWeb's throughput at 15 megabits per kilogram while they estimate SpaceX's throughput at 13.9 megabits per kilogram.

I'm still reading through the paper, personally - I'm not seeing these numbers anywhere? I'm guessing you personally calculated them off of some of the figures in the paper? I can certainly believe the numbers, as the bandwidth/sat on Starlink is higher, but the OneWeb satellite mass is quite a bit smaller.

The "efficiency" mentioned in the paper refers to how much of the hardware bandwidth on each satellite is utilizable due to antenna, orbit design, and other parameters. The number, with some assumptions, is 58% for Telesat, 25.5% for SpaceX, and 21.7% for OneWeb. It varies a lot on ground station support - SpaceX requires quite a few more ground stations than everyone else, especially without ISL, simply due to the large number of satellites.

I think the thing we can conclude from this paper with quite some certainty is that if all of these systems were in orbit today, Telesat is easily the most efficient from a utilization (not payload mass) standpoint. They plan on flying fewer, bigger birds with a heck of a lot more capability per bird, with a fairly well thought out launch constellation that efficiently emphasizes population distribution on earth.
Title: Re: Starlink : General Discussion - Thread 2
Post by: thirtyone on 09/16/2019 09:17 pm
I have a question - perhaps for someone with better knowledge of orbital mechanics and launch costs. Is it really that much easier/cheaper to launch satellites into the 89 degree inclination? The biggest issue with the OneWeb constellation that makes its performance so poor is that that particular orbital plane grossly overemphasizes coverage in the north and south poles, where, well, very few people actually live. (See figure 4). I assume there's a launch cost reason for this design parameter.

edit:
The paper specifically says:
Quote
As mentioned before, OneWeb’s system is heavily constrained by the satellite-to-user links, which is the main reason for its lower overall performance in terms of data-rate.

I am not sure how accurate my interpretation (orbital inclinations) is, but it would seem like part of the problem. In general, Telesat went for bigger, more capable birds which require more expensive ground equipment; OneWeb went for lower risk and lower complexity to be first to market; and SpaceX took the approach of launching an extremely large constellation, with more capable satellites, which has the risk of still requiring quite a bit of ground support. My personal feeling is that the only reason SpaceX has a chance of pulling this off is that they are vertically integrated and have substantially lower launch costs than anyone else.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 09/16/2019 10:10 pm
I have a question - perhaps for someone with better knowledge of orbital mechanics and launch costs. Is it really that much easier/cheaper to launch satellites into the 89 degree inclination? The biggest issue with the OneWeb constellation that makes its performance so poor is that that particular orbital plane grossly overemphasizes coverage in the north and south poles, where, well, very few people actually live. (See figure 4). I assume there's a launch cost reason for this design parameter.

It's not easier or cheaper to launch into a polar orbit.  Choosing polar orbits can simplify the system design because one inclination gives you coverage of the entire planet.  SpaceX doesn't care so much about global coverage, they want to concentrate on the populated areas with some higher inclination coverage later on.  Telesat's system is a mix of polar and lower inclination.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gaballard on 09/16/2019 10:12 pm
I have a question - perhaps for someone with better knowledge of orbital mechanics and launch costs. Is it really that much easier/cheaper to launch satellites into the 89 degree inclination? The biggest issue with the OneWeb constellation that makes its performance so poor is that that particular orbital plane grossly overemphasizes coverage in the north and south poles, where, well, very few people actually live. (See figure 4). I assume there's a launch cost reason for this design parameter.

edit:
The paper specifically says:
Quote
As mentioned before, OneWeb’s system is heavily constrained by the satellite-to-user links, which is the main reason for its lower overall performance in terms of data-rate.

I am not sure how accurate my interpretation (orbital inclinations) is, but it would seem like part of the problem. In general, Telesat went for bigger, more capable birds which require more expensive ground equipment; OneWeb went for lower risk and lower complexity to be first to market; and SpaceX took the approach of launching an extremely large constellation, with more capable satellites, which has the risk of still requiring quite a bit of ground support. My personal feeling is that the only reason SpaceX has a chance of pulling this off is that they are vertically integrated and have substantially lower launch costs than anyone else.

Polar orbits will slowly precess over time, allowing the birds to stay over the same locations on Earth's surface w/o needing a lot of stationkeeping deltaV. They'll also be in sunlight nearly all the time, so they won't need to bring a lot of batteries with them.
Title: Re: Starlink : General Discussion - Thread 2
Post by: thirtyone on 09/16/2019 10:14 pm
Here's an article on optical comsats, with an intriguing quote from the CEO of Space Micro, who mentions that their space laser system will be in orbit "later this year." I wonder if they are actually quietly a supplier for perhaps the first generation of SpaceX satellites (I know SpaceX likes doing things in-house, but perhaps this was a feasibility study). Or maybe one of their competitors testing a similar system. Or some HFT trading company using it for some latency shenanigans.

anyone have any guesses on this? The CEO vaguely describes the target satellite in the video from the March 20, 2019 directed energy summit around 30:00.

https://www.boozallen.com/d/multimedia/2019-directed-energy-summit-video-highlights.html

- they try to use commercial components for the communication side of things, keeping costs low (everything up to the fiber - they build the steering mechanism and optics)
- "flying later this year" in LEO
- 100Gbps performance
- Low-SWaP, the size of "two Dells," whatever that means
- were able to find someone who was "well-funded and wanted to do this"

Would just be useful to get a sense of how well a modern sat-sat laser link functions if we knew the sat it's on.
Title: Re: Starlink : General Discussion - Thread 2
Post by: ncb1397 on 09/16/2019 10:17 pm
I have a question - perhaps for someone with better knowledge of orbital mechanics and launch costs. Is it really that much easier/cheaper to launch satellites into the 89 degree inclination? The biggest issue with the OneWeb constellation that makes its performance so poor is that that particular orbital plane grossly overemphasizes coverage in the north and south poles, where, well, very few people actually live. (See figure 4). I assume there's a launch cost reason for this design parameter.

edit:
The paper specifically says:
Quote
As mentioned before, OneWeb’s system is heavily constrained by the satellite-to-user links, which is the main reason for its lower overall performance in terms of data-rate.

I am not sure how accurate my interpretation (orbital inclinations) is, but it would seem like part of the problem. In general, Telesat went for bigger, more capable birds which require more expensive ground equipment; OneWeb went for lower risk and lower complexity to be first to market; and SpaceX took the approach of launching an extremely large constellation, with more capable satellites, which has the risk of still requiring quite a bit of ground support. My personal feeling is that the only reason SpaceX has a chance of pulling this off is that they are vertically integrated and have substantially lower launch costs than anyone else.

Polar orbits will slowly precess over time, allowing the birds to stay over the same locations on Earth's surface w/o needing a lot of stationkeeping deltaV. They'll also be in sunlight nearly all the time, so they won't need to bring a lot of batteries with them.

If they were always sunlit, you will get internet outage at night time. Anyways, while polar users (planes, settlements, boats, etc.) aren't numerous, they can tend to have deeper pockets. The recent nearly billion dollar contract that Iridium has signed with the DoD demonstrates that.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 09/16/2019 10:23 pm
Polar orbits will slowly precess over time, allowing the birds to stay over the same locations on Earth's surface w/o needing a lot of stationkeeping deltaV. They'll also be in sunlight nearly all the time, so they won't need to bring a lot of batteries with them.

LEO comsats don't need to be in SSO, and I don't think any of the major constellations plan to use SSO.  There is a particular orbit that stays in sunlight and if you have a constellation of multiple planes how are you planning to keep all of them in that orbit at the same time?
Title: Re: Starlink : General Discussion - Thread 2
Post by: Comga on 09/16/2019 11:04 pm

Lets break it down how I would do the implementation. The optical layout would be something like this:

(snip)

As said earlier, IT TAKES A LASERCOMM ENGINEER

This is too simplistic and impractical.  None of those elements would work without significant increases in complexity.
There are decades of technology development behind lasercomm. 
You can't just make this stuff up.
Don't Poo Poo the difficult and cost.
Space instrumentation is really difficult.
And as someone else has in their tag line, engineering is done with numbers.  Discussion without numbers is just opinion.
And opinions are like other things everyone has.  ;)
We aren't going to get there on the back of an envelope.
Title: Re: Starlink : General Discussion - Thread 2
Post by: cosmicvoid on 09/17/2019 03:41 am
Haven't seen this news item yet on this forum, so here is Spacex's plan to shuffle its constellation:

https://finance.yahoo.com/news/spacex-wants-rearrange-starlink-satellites-002119185.html
Title: Re: Starlink : General Discussion - Thread 2
Post by: Semmel on 09/17/2019 06:55 am
No need to get cranky. I didnt try to 'solve' lasercom, I try to get a good enough understanding of the design quantitatively, not qualitatively, in order to understand what the biggest or hardest problem is. To do so, one needs to have a rudimentary idea of the design.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Nomadd on 09/17/2019 07:03 am

Lets break it down how I would do the implementation. The optical layout would be something like this:

(snip)

As said earlier, IT TAKES A LASERCOMM ENGINEER

This is too simplistic and impractical.  None of those elements would work without significant increases in complexity.
There are decades of technology development behind lasercomm. 
You can't just make this stuff up.
Don't Poo Poo the difficult and cost.
Space instrumentation is really difficult.
And as someone else has in their tag line, engineering is done with numbers.  Discussion without numbers is just opinion.
And opinions are like other things everyone has.  ;)
We aren't going to get there on the back of an envelope.
Calm down Jethro. There aren't too many people on this rock that know more about collecting photons than Semmel, and he's just fishing for more information.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Semmel on 09/17/2019 10:25 pm
Calm down Jethro. There aren't too many people on this rock that know more about collecting photons than Semmel, and he's just fishing for more information.

Lets not have a discussion based on authority, I have no clue about laser-com for instance. But I would love to understand the engineering challenges as they seem to be fun things to think about. I dont have time to go through the other information that was provided, kind of buried in work for the week. But we will get there.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Tywin on 09/18/2019 12:06 pm
Starlink in Tesla?

https://twitter.com/thesheetztweetz/status/1173978862625202184
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 09/18/2019 01:59 pm
Starlink in Tesla?

https://twitter.com/thesheetztweetz/status/1173978862625202184

Notes like that tend to be written by people that don't have a freakin' clue about one or both of the things they're trying to tie together.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Nomadd on 09/18/2019 04:29 pm
Starlink in Tesla?

https://twitter.com/thesheetztweetz/status/1173978862625202184

Notes like that tend to be written by people that don't have a freakin' clue about one or both of the things they're trying to tie together.
It does sound like he just threw a bunch of random terms together that he didn't understand.
Title: Re: Starlink : General Discussion - Thread 2
Post by: AC in NC on 09/18/2019 05:51 pm
Starlink in Tesla?
Notes like that tend to be written by people that don't have a freakin' clue about one or both of the things they're trying to tie together.
It does sound like he just threw a bunch of random terms together that he didn't understand.

Not sure exactly what the criticism is of the note.

In intro paragraph of the MS Report contains the exact sentence tweeted:

"SpaceX is accelerating plans to deploy and commercialize satellite broadband with significant implications for capital demands, valuation… and potential strategic implications for Tesla."  It seems like people are reading that as capital demand/valuation implications for Tesla rather than those for SpaceX and Synergies with Tesla.

The actual Morgan Stanley Research Report (https://www.documentcloud.org/documents/6416324-SPACE-20190917-SpaceX-valuation-Morgan-Stanley.html) is reasonably straightforward with no outrageous claims.  The only Tesla statement in the body of the report is a fairly pedestrian remark: 

                            (https://i.imgur.com/SOZEa0H.jpg)

The report has some interesting (if perhaps spitballed) market opportunity/revenue projections through 2040.

And the main thrust of the remark simply seems to be a fairly uncontroversial:

MS thinks investors might be underappreciating the "strategic relationship and [revenue opportunity] synergies" between SX and TSLA.  That single simple statement just seems related to a section (albeit not huge $-wise) in the market opportunity/revenue projections on Autonomous Autombiles.

While in general those criticisms regularly apply, I don't see the reason for using them against either the tweet or MS's Research Report.
Title: Re: Starlink : General Discussion - Thread 2
Post by: RedLineTrain on 09/18/2019 07:05 pm
MS thinks investors might be underappreciating the "strategic relationship and [revenue opportunity] synergies" between SX and TSLA.  That single simple statement just seems related to a section (albeit not huge $-wise) in the market opportunity/revenue projections on Autonomous Autombiles.

The problem with that supposition is that Musk has said the terminals won't go into Tesla cars.  So the analysts must be banking on Musk reversing himself.

Morgan Stanley has been fishing this angle for years, despite Musk shutting it down.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Wudizzle on 09/18/2019 07:12 pm
MS thinks investors might be underappreciating the "strategic relationship and [revenue opportunity] synergies" between SX and TSLA.  That single simple statement just seems related to a section (albeit not huge $-wise) in the market opportunity/revenue projections on Autonomous Autombiles.

The problem with that supposition is that Musk has said the terminals won't go into Tesla cars.  So the analysts must be banking on Musk reversing himself.

Morgan Stanley has been fishing this angle for years, despite Musk shutting it down.

To be fair, Musk has changed direction and/or reversed himself many times publicly.

To further be fair, he doesn't have much of a history of under-selling a potential market.

I guess that evens out to 'meh.'
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 09/18/2019 07:24 pm
One thing with financial analysts pushing satellite connectivity as synergistic with autonomous cars:  the people actually working on autonomous cars say they aren't building their systems to need that connectivity.
Title: Re: Starlink : General Discussion - Thread 2
Post by: speedevil on 09/18/2019 07:26 pm
One thing with financial analysts pushing satellite connectivity as synergistic with autonomous cars:  the people actually working on autonomous cars say they aren't building their systems to need that connectivity.
And more than 'the people' in general, the whole presentation from Elon and friends on 'Autonomy Day' just several months ago went into great detail how their philosophy relies on neither accurate GPS or high bandwidth distant control.
Title: Re: Starlink : General Discussion - Thread 2
Post by: envy887 on 09/18/2019 07:29 pm
One thing with financial analysts pushing satellite connectivity as synergistic with autonomous cars:  the people actually working on autonomous cars say they aren't building their systems to need that connectivity.

The people in the cars need the connectivity. Must have some way to watch cat videos while the car is driving you around, since you don't have all that annoying driving to take up your time :D
Title: Re: Starlink : General Discussion - Thread 2
Post by: AC in NC on 09/18/2019 07:35 pm
The problem with that supposition is that Musk has said the terminals won't go into Tesla cars.  So the analysts must be banking on Musk reversing himself.

Morgan Stanley has been fishing this angle for years, despite Musk shutting it down.

To be fair, Musk has changed direction and/or reversed himself many times publicly.
To further be fair, he doesn't have much of a history of under-selling a potential market.
I guess that evens out to 'meh.'

Strong points in both posts.  I'd not realized (or forgot about) Musk's shutting that down.  MS didn't have it as any large opportunity anyway.  Sort of wondered why they included it.

Just didn't seem to be such a stretch compared to the typical manner in which journalists butcher technical details.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Rondaz on 09/18/2019 08:40 pm
Morgan Stanley estimates SpaceX's current value at around  $52.2 billion. Looking forward, they estimate $5 to $120 billion valuations. (Not very precise :-). Seeing is believing.

https://twitter.com/larrypress/status/1174417773285429248
Title: Re: Starlink : General Discussion - Thread 2
Post by: Herb Schaltegger on 09/18/2019 10:41 pm
One thing with financial analysts pushing satellite connectivity as synergistic with autonomous cars:  the people actually working on autonomous cars say they aren't building their systems to need that connectivity.

True but there are many kinds of automotive telematics systems that currently use "stealth" cellular modems in automobiles and long-haul trucks (that is, cellular connectivity for system updates and status reports ... "telemetry" if you will ... ) totally apart from the voice cell phones carried by the drivers. Plus the automotive systems that do entertainment software updates piggybacked on commercial satellite radio signals or other networks. Large trucking companies do driver-oversight and route routing/planning through cellular and satellite as well, and have for years.

Having their own "in-house" network available for all these features could prove very useful for Tesla's own longer-term plans, especially if electric freight trucks become a significant player in that market. These applications are totally separate from the driver logging in to check Facebook and Twitter while the Auto Pilot drives her around.
Title: Re: Starlink : General Discussion - Thread 2
Post by: OTV Booster on 09/19/2019 01:08 am
I threw out a question earlier and got no response. I’d like to think its because other subthreads got hot. Maybe it’s so dumb it didn’t warrant a response, but I’d rather be told that than be left wondering. I promise not to cry.

I was asking about the possibility of two different types of sats. Lower orbit sats would do end user contact and higher level sats would specialize in ISL and high bandwidth ground links to hit copper. The low sats would have lasers to pass data to the high sats. In effect the high sats would be routers.

The  high sats are still LEO and not really all that high. I also recognize SX likes commonality but also recognize the are very practical people. Is there any sense in this idea or does it cause more trouble than it’s worth?

Pros:
-The low sats would not need complicated routing tables.  If its not in the local table, send it to a router and let the big boy figure it out. Makes the sat less expensive.
-The low sats would never be relaying the data from other sats. The laser coms would need less bandwidth and have to deal with only one other sat at a time (maybe two during a handoff).  Less expensive system.
-The low sats that decay the fastest, would be relatively inexpensive.
-the high sats would focus on routing, not customer contact. Simplified design, in that respect.
-Things I haven’t thought of.

Cons:
-The the handoff from one router to another might be tricky.
-maybe less resilient to loss of a sat. Maybe.
- high sats would need lasers to link to many (several?) low sats and many (several?) other router sats.
-the high sats would be relatively expensive. Maybe so much that it is not offset by the inexpensive low sats.
-things I haven’t thought of.


Phil
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 09/19/2019 01:24 am
The  high sats are still LEO and not really all that high. I also recognize SX likes commonality but also recognize the are very practical people. Is there any sense in this idea or does it cause more trouble than it’s worth?

I really don't see the point of doing that.  For the Ku/Ka-band sats the links to users and the links to gateways are on different frequency bands (other than the first 60 test sats).  Having different sats specialize in communicating with users or gateways would just hurt the overall bandwidth.  They can also add V-band communications at some point to increase the bandwidth of all sats (they are authorized for ~4k Ku/Ka/V-band and ~7k V-band only).
Title: Re: Starlink : General Discussion - Thread 2
Post by: Robotbeat on 09/19/2019 03:31 am
MS thinks investors might be underappreciating the "strategic relationship and [revenue opportunity] synergies" between SX and TSLA.  That single simple statement just seems related to a section (albeit not huge $-wise) in the market opportunity/revenue projections on Autonomous Autombiles.

The problem with that supposition is that Musk has said the terminals won't go into Tesla cars.  So the analysts must be banking on Musk reversing himself.

Morgan Stanley has been fishing this angle for years, despite Musk shutting it down.
Sometimes Musk intentionally downplays things. Like the idea that the Supercharging network is a moat (it absolutely is, although not a permanent one).

Personally, I think the relationship makes more sense from a sales/marketing perspective. Tesla has stores everywhere and is a powerful consumer brand already. SpaceX only sells mugs and t-shirts (etc) to consumers.

Solar roof and Starlink terminal installed at the same time. Makes sense.
Title: Re: Starlink : General Discussion - Thread 2
Post by: ninjaneer on 09/19/2019 04:14 am
Has there been any mention since the May media call of whether Starlink will be sold directly or resold through ISPs?
Title: Re: Starlink : General Discussion - Thread 2
Post by: Roy_H on 09/19/2019 05:31 am
MS thinks investors might be underappreciating the "strategic relationship and [revenue opportunity] synergies" between SX and TSLA.  That single simple statement just seems related to a section (albeit not huge $-wise) in the market opportunity/revenue projections on Autonomous Autombiles.

The problem with that supposition is that Musk has said the terminals won't go into Tesla cars.  So the analysts must be banking on Musk reversing himself.

Morgan Stanley has been fishing this angle for years, despite Musk shutting it down.

Tesla is also selling solar systems for houses. Could be that satellite transceivers for houses is the synergy, not cars.
Title: Re: Starlink : General Discussion - Thread 2
Post by: MikeAtkinson on 09/19/2019 07:20 am
MS thinks investors might be underappreciating the "strategic relationship and [revenue opportunity] synergies" between SX and TSLA.  That single simple statement just seems related to a section (albeit not huge $-wise) in the market opportunity/revenue projections on Autonomous Autombiles.

The problem with that supposition is that Musk has said the terminals won't go into Tesla cars.  So the analysts must be banking on Musk reversing himself.

Morgan Stanley has been fishing this angle for years, despite Musk shutting it down.

But the gateways may be co-located with Tesla service and delivery centers, there are quite a few of these now and more are being opened all the time.
Title: Re: Starlink : General Discussion - Thread 2
Post by: MikeAtkinson on 09/19/2019 07:26 am
One thing with financial analysts pushing satellite connectivity as synergistic with autonomous cars:  the people actually working on autonomous cars say they aren't building their systems to need that connectivity.

The people in the cars need the connectivity. Must have some way to watch cat videos while the car is driving you around, since you don't have all that annoying driving to take up your time :D

Satellite connectivity does not work well in tunnels or underground parking. 5G and 4G will provide majority of connectivity, with just perhaps an optional package for StarLink for those who spend time away from civilization.
Title: Re: Starlink : General Discussion - Thread 2
Post by: MikeAtkinson on 09/19/2019 07:50 am
Tesla is also selling solar systems for houses. Could be that satellite transceivers for houses is the synergy, not cars.

Solar and PowerWall are much better for synergies than cars. For solar in particular they already have to get access to the roof, so adding a phase array at the same time is very cheap in installation cost.
Title: Re: Starlink : General Discussion - Thread 2
Post by: OTV Booster on 09/19/2019 01:00 pm
The  high sats are still LEO and not really all that high. I also recognize SX likes commonality but also recognize the are very practical people. Is there any sense in this idea or does it cause more trouble than it’s worth?

I really don't see the point of doing that.  For the Ku/Ka-band sats the links to users and the links to gateways are on different frequency bands (other than the first 60 test sats).  Having different sats specialize in communicating with users or gateways would just hurt the overall bandwidth.  They can also add V-band communications at some point to increase the bandwidth of all sats (they are authorized for ~4k Ku/Ka/V-band and ~7k V-band only).

I’m casting about trying to figure a way to transition from a system without ISL to one with it, without decommissioning sats prematurely. Lots of moving parts. Little understanding, but hey that never stopped anybody <g>.

Phil
Title: Re: Starlink : General Discussion - Thread 2
Post by: OTV Booster on 09/19/2019 01:09 pm
Tesla is also selling solar systems for houses. Could be that satellite transceivers for houses is the synergy, not cars.

Solar and PowerWall are much better for synergies than cars. For solar in particular they already have to get access to the roof, so adding a phase array at the same time is very cheap in installation cost.


It also gives an opportunity to wire in operating and backup power without running through the inverter/rectifier mess.  Coms are a good thing to have during an outage.


Phil
Title: Re: Starlink : General Discussion - Thread 2
Post by: FutureSpaceTourist on 09/19/2019 07:15 pm
https://twitter.com/jeff_foust/status/1174749757329199104

Quote
Goldstein: with Aeolus/Starlink conjunction, got the software bug that prevents communications worked out, learned a lot. Agree with ESA this can’t be managed on an individual basis by email alone; need some automation. #AMOS20th


https://twitter.com/jeff_foust/status/1174755098582323200

Quote
Goldstein: SpaceX has done 21 avoidance maneuvers autonomously among the Starlink satellites; all involved non-maneuverable objects. #AMOS20th
Title: Re: Starlink : General Discussion - Thread 2
Post by: RoboGoofers on 09/20/2019 02:15 am
The  high sats are still LEO and not really all that high. I also recognize SX likes commonality but also recognize the are very practical people. Is there any sense in this idea or does it cause more trouble than it’s worth?

I really don't see the point of doing that.  For the Ku/Ka-band sats the links to users and the links to gateways are on different frequency bands (other than the first 60 test sats).  Having different sats specialize in communicating with users or gateways would just hurt the overall bandwidth.  They can also add V-band communications at some point to increase the bandwidth of all sats (they are authorized for ~4k Ku/Ka/V-band and ~7k V-band only).

I’m casting about trying to figure a way to transition from a system without ISL to one with it, without decommissioning sats prematurely. Lots of moving parts. Little understanding, but hey that never stopped anybody <g>.

Phil
they can use the non isl sats as backup or move them around to other inclinations to extend service latitude. Or they could dunk them all. Once they do their job (getting starlink up and making money) they will have paid for themselves and their replacement.
Title: Re: Starlink : General Discussion - Thread 2
Post by: woods170 on 09/20/2019 07:22 am
Has there been any mention since the May media call of whether Starlink will be sold directly or resold through ISPs?

SpaceX is not in the business of reselling its product thru third parties.


That applies to Musk's other businesses as well.
Title: Re: Starlink : General Discussion - Thread 2
Post by: envy887 on 09/20/2019 12:30 pm
Has there been any mention since the May media call of whether Starlink will be sold directly or resold through ISPs?

SpaceX is not in the business of reselling its product thru third parties.


That applies to Musk's other businesses as well.

How would you describe the SSO-A launch then? Spaceflight resold the launch capacity if bought form SpaceX.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 09/20/2019 01:32 pm
Has there been any mention since the May media call of whether Starlink will be sold directly or resold through ISPs?

SpaceX is not in the business of reselling its product thru third parties.
That applies to Musk's other businesses as well.

In other countries SpaceX may be required to partner with local companies.  If they're targeting the backhaul market then that won't be direct to end-users either.
Title: Re: Starlink : General Discussion - Thread 2
Post by: matthewkantar on 09/20/2019 01:58 pm
How would you describe the SSO-A launch then? Spaceflight resold the launch capacity if bought form SpaceX.

They have cut out the middle person there, they are now selling those types of rides directly.
Title: Re: Starlink : General Discussion - Thread 2
Post by: rsdavis9 on 09/20/2019 02:26 pm
The  high sats are still LEO and not really all that high. I also recognize SX likes commonality but also recognize the are very practical people. Is there any sense in this idea or does it cause more trouble than it’s worth?

I really don't see the point of doing that.  For the Ku/Ka-band sats the links to users and the links to gateways are on different frequency bands (other than the first 60 test sats).  Having different sats specialize in communicating with users or gateways would just hurt the overall bandwidth.  They can also add V-band communications at some point to increase the bandwidth of all sats (they are authorized for ~4k Ku/Ka/V-band and ~7k V-band only).

I’m casting about trying to figure a way to transition from a system without ISL to one with it, without decommissioning sats prematurely. Lots of moving parts. Little understanding, but hey that never stopped anybody <g>.

Phil
they can use the non isl sats as backup or move them around to other inclinations to extend service latitude. Or they could dunk them all. Once they do their job (getting starlink up and making money) they will have paid for themselves and their replacement.

and based upon the traffic destination they could decide whether to use ISL and therefore stay in space or just bounce down to local ground station for delivery. So packet by packet use both.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Barley on 09/20/2019 02:31 pm

I’m casting about trying to figure a way to transition from a system without ISL to one with it, without decommissioning sats prematurely. Lots of moving parts. Little understanding, but hey that never stopped anybody

The initial partial constellation can provide a regional overlay to serve more people with a better quality of service in its coverage area.   I imagine it will continue to operate until the newer satellites are fully able to meet demand, or there are so many satellites that the old satellites cannot be operated without interfering with the new ones.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 09/20/2019 02:39 pm
Retiring sats early also doesn't help them meet their deployment milestones.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Rondaz on 09/20/2019 02:53 pm
Internet returning in Bermuda following  #HurricaneHumberto. Live connectivity stats here: https://map.internetintel.oracle.com/?root=national&country=BM …

https://twitter.com/InternetIntel/status/1174987061725671424
Title: Re: Starlink : General Discussion - Thread 2
Post by: OTV Booster on 09/20/2019 04:36 pm
The  high sats are still LEO and not really all that high. I also recognize SX likes commonality but also recognize the are very practical people. Is there any sense in this idea or does it cause more trouble than it’s worth?

I really don't see the point of doing that.  For the Ku/Ka-band sats the links to users and the links to gateways are on different frequency bands (other than the first 60 test sats).  Having different sats specialize in communicating with users or gateways would just hurt the overall bandwidth.  They can also add V-band communications at some point to increase the bandwidth of all sats (they are authorized for ~4k Ku/Ka/V-band and ~7k V-band only).

I’m casting about trying to figure a way to transition from a system without ISL to one with it, without decommissioning sats prematurely. Lots of moving parts. Little understanding, but hey that never stopped anybody <g>.

Phil
they can use the non isl sats as backup or move them around to other inclinations to extend service latitude. Or they could dunk them all. Once they do their job (getting starlink up and making money) they will have paid for themselves and their replacement.
Yup, this approach would work. The current crop is mostly engineer ‘toys’ and could easily be expended. But the original question, which arose while I was looking at integrating isl & non isl sats does have some broader logic.

If a customer sat only interconnect to isl/gateway sats they only need laser bandwidth equal to their customer bandwidth. For isl receive, bandwidth would depend on which end does the buffering. If the buffering is done on the big isl sat the customer sat becomes simpler, smaller, lighter and less expensive. The shorter lifetime due to lower orbits would be less of a hit.

ISL (geometric) routing also becomes simpler for the customer sats. With the architecture as it stands now a sat a sat can do isl forward or back within its plane or to either side at a range of angles to adjacent planes. With dedicated isl sats a customer sat only need pick an isl sat until the angle or distance causes problems. It then does a handoff to another. If the handoff logic is handled by the isl sat the customer sat becomes yet simpler.

The ground gateways become simpler in that they would beam form to fewer sats. In turn, each beam would have to carry greater bandwidth.

Each isl/gateway downlink sat would be bigger, heavier, more complex and more expensive. As an offset, they would be in the higher orbits and decay slower. The expense might justify more orbit keeping props.

Gongora (I think) said that system bandwidth would go down with dedicated gateway downlink without further explanation other than a terse listing of allocated bands and numbers that I assume to be the licensed portions of these bands. Full disclosure: I am not an RF engineer. Any explanation warmly welcome.

Assuming (maybe a bad assumption) that redistributing the gateway bandwidth will not impact total available bandwidth, and assuming there is no hole in my logic (not assured), ISTM that it becomes a question of total full up life cycle costs between the two architectures plus development costs.

Phil
Title: Re: Starlink : General Discussion - Thread 2
Post by: ninjaneer on 09/20/2019 04:48 pm
Has there been any mention since the May media call of whether Starlink will be sold directly or resold through ISPs?

SpaceX is not in the business of reselling its product thru third parties.

That applies to Musk's other businesses as well.

I very much hope that applies, but has there been any actual evidence to support that claim?  If they do intend to start selling modems next year, then there should be some trace signs of customer support and call center development.  A best effort lead time would be 180-270 days.
Title: Re: Starlink : General Discussion - Thread 2
Post by: OTV Booster on 09/20/2019 04:49 pm
The  high sats are still LEO and not really all that high. I also recognize SX likes commonality but also recognize the are very practical people. Is there any sense in this idea or does it cause more trouble than it’s worth?

I really don't see the point of doing that.  For the Ku/Ka-band sats the links to users and the links to gateways are on different frequency bands (other than the first 60 test sats).  Having different sats specialize in communicating with users or gateways would just hurt the overall bandwidth.  They can also add V-band communications at some point to increase the bandwidth of all sats (they are authorized for ~4k Ku/Ka/V-band and ~7k V-band only).

I’m casting about trying to figure a way to transition from a system without ISL to one with it, without decommissioning sats prematurely. Lots of moving parts. Little understanding, but hey that never stopped anybody <g>.

Phil
they can use the non isl sats as backup or move them around to other inclinations to extend service latitude. Or they could dunk them all. Once they do their job (getting starlink up and making money) they will have paid for themselves and their replacement.

and based upon the traffic destination they could decide whether to use ISL and therefore stay in space or just bounce down to local ground station for delivery. So packet by packet use both.
If the destination is in the local table it would go direct. If not, it depends on whether isl is available or not. If not it would go to the ground gateway and forward onto copper. If available, the packet would go out isl to another sat for forwarding. To an adjacent sat in one architecture or an isl sat in another.

Phil
Title: Re: Starlink : General Discussion - Thread 2
Post by: Barley on 09/20/2019 07:33 pm
The shorter lifetime due to lower orbits would be less of a hit.
If satellite lifespan at 450km is an actual problem you can add years to it by adding 1 kg of krypton to each bird, so 4000kg total upmass.  Quite a bit cheaper than adding an extra layer of satellites.

If routing is a problem you can add hierarchical routing or share the routing load without an extra physical tier.  In any case don't try to simplify software by complexifying hardware unless the software group asks for it.  And then give some thought to what they asked for.  The number of times I asked for cache and got flops and a thermal management problem ... .
Title: Re: Starlink : General Discussion - Thread 2
Post by: RedLineTrain on 09/20/2019 09:03 pm
Has there been any mention since the May media call of whether Starlink will be sold directly or resold through ISPs?

SpaceX is not in the business of reselling its product thru third parties.

That applies to Musk's other businesses as well.

I very much hope that applies, but has there been any actual evidence to support that claim?  If they do intend to start selling modems next year, then there should be some trace signs of customer support and call center development.  A best effort lead time would be 180-270 days.

The evidence is that there have been no announced marketing deals for Starlink.

No need to make this overly complicated.  Musk will announce it on Twitter with a sign-up/order page on Starlink.com.  They will get a million takers depending on the required deposit, from which they can pick and choose geographies for a beta-ish service.

At first, Starlink customer service can be co-located with Tesla's in Las Vegas.  Built-out in Las Vegas or elsewhere as necessary.
Title: Re: Starlink : General Discussion - Thread 2
Post by: cro-magnon gramps on 09/21/2019 10:55 am
Has there been any mention since the May media call of whether Starlink will be sold directly or resold through ISPs?

SpaceX is not in the business of reselling its product thru third parties.

That applies to Musk's other businesses as well.

I very much hope that applies, but has there been any actual evidence to support that claim?  If they do intend to start selling modems next year, then there should be some trace signs of customer support and call center development.  A best effort lead time would be 180-270 days.

The evidence is that there have been no announced marketing deals for Starlink.

No need to make this overly complicated.  Musk will announce it on Twitter with a sign-up/order page on Starlink.com.  They will get a million takers depending on the required deposit, from which they can pick and choose geographies for a beta-ish service.

At first, Starlink customer service can be co-located with Tesla's in Las Vegas.  Built-out in Las Vegas or elsewhere as necessary.
As there is the southern border of Canada to consider in their first iteration of Satellite Service, after 6 launches, do you think that they may utilize Musk's experience with Paypal to enable cross border sign up and payments... Or something similar... or is there some international barrier that I am not aware of?
Title: Re: Starlink : General Discussion - Thread 2
Post by: mlindner on 09/21/2019 02:02 pm
In case it wasn't mentioned before, with the potential close approach to ESA's satellite. That weekend was labor day weekend in the US with the close approach right on labor day, which with the on-call system failure (very commonly used in the software world) there would be literally no person in place who would actually have seen any email. So it's a perfect storm of unfortunate situations (and ESA was still wrong to directly attack SpaceX for it and push that idea in the media).

No SpaceX and ESA are not lacking communication. No SpaceX is not acting incorrectly. They're acting just as well as anyone else in the space industry with regards to space junk, if not better than most. They're just new to the process and their systems aren't operational mode yet which will explain any oversight that takes places.
Title: Re: Starlink : General Discussion - Thread 2
Post by: DigitalMan on 09/21/2019 04:10 pm
In case it wasn't mentioned before, with the potential close approach to ESA's satellite. That weekend was labor day weekend in the US with the close approach right on labor day, which with the on-call system failure (very commonly used in the software world) there would be literally no person in place who would actually have seen any email. So it's a perfect storm of unfortunate situations (and ESA was still wrong to directly attack SpaceX for it and push that idea in the media).

No SpaceX and ESA are not lacking communication. No SpaceX is not acting incorrectly. They're acting just as well as anyone else in the space industry with regards to space junk, if not better than most. They're just new to the process and their systems aren't operational mode yet which will explain any oversight that takes places.

I found it interesting Starlink performed 21 autonomous avoidance maneuvers to avoid objects that had no propulsion.  Odd that the media isn't talking about it especially since it is a new thing, no?
Title: Re: Starlink : General Discussion - Thread 2
Post by: mlindner on 09/21/2019 06:06 pm
In case it wasn't mentioned before, with the potential close approach to ESA's satellite. That weekend was labor day weekend in the US with the close approach right on labor day, which with the on-call system failure (very commonly used in the software world) there would be literally no person in place who would actually have seen any email. So it's a perfect storm of unfortunate situations (and ESA was still wrong to directly attack SpaceX for it and push that idea in the media).

No SpaceX and ESA are not lacking communication. No SpaceX is not acting incorrectly. They're acting just as well as anyone else in the space industry with regards to space junk, if not better than most. They're just new to the process and their systems aren't operational mode yet which will explain any oversight that takes places.

I found it interesting Starlink performed 21 autonomous avoidance maneuvers to avoid objects that had no propulsion.  Odd that the media isn't talking about it especially since it is a new thing, no?

To be honest, I didn't know that either and I can't find it via google. Got a link?
Title: Re: Starlink : General Discussion - Thread 2
Post by: docmordrid on 09/21/2019 06:12 pm
>
To be honest, I didn't know that either and I can't find it via google. Got a link?

Sept 3,

Jonathan O'Callaghan ✓ @Astro_Jonny

Some additional bits of useful information about #Aeolus/#Starlink from SpaceX:

- Starlink 44 is operational and capable of avoidance maneuvers if necessary

- In three months the Starlink fleet has performed 16 collision avoidance maneuvers without any manual input (!)

https://twitter.com/Astro_Jonny/status/1168976820349415430
Title: Re: Starlink : General Discussion - Thread 2
Post by: mlindner on 09/21/2019 06:18 pm
>
To be honest, I didn't know that either and I can't find it via google. Got a link?

Jonathan O'Callaghan ✓ @Astro_Jonny

Some additional bits of useful information about #Aeolus/#Starlink from SpaceX:

- Starlink 44 is operational and capable of avoidance maneuvers if necessary

- In three months the Starlink fleet has performed 16 collision avoidance maneuvers without any manual input (!)

https://twitter.com/Astro_Jonny/status/1168976820349415430 (http://"https://twitter.com/Astro_Jonny/status/1168976820349415430")

Nitpick, don't insert quotes into the URL when linking it... It just prevents you from clicking it. Just copy paste it and it works fine. A lot of people do this on this forum and I don't understand why.

https://twitter.com/Astro_Jonny/status/1168976820349415430
Title: Re: Starlink : General Discussion - Thread 2
Post by: CuddlyRocket on 09/21/2019 06:31 pm
Has there been any mention since the May media call of whether Starlink will be sold directly or resold through ISPs?

SpaceX is not in the business of reselling its product thru third parties.

That applies to Musk's other businesses as well.

There is a difference between selling to a wholesaler and having agents conduct sales on your behalf. I see no reason why SpaceX would turn down a customer simply because they were an ISP rather than an individual, corporation or other entity. It's likely to be much more cost-effective for a group of individuals (say in an isolated community) to contract with an ISP (if one is available) who have themselves contracted with SpaceX for long-distance communications than it is for them each to individually contract with SpaceX direct. It is also more likely to be cost-effective for SpaceX to have one larger customer than a number of small individual ones.
Title: Re: Starlink : General Discussion - Thread 2
Post by: docmordrid on 09/21/2019 06:34 pm
Further,

https://spacenews.com/better-coordination-needed-among-operators-to-avoid-potential-collisions/

Quote
The operational Starlink satellites do have the autonomous system in place. Goldstein said that, as of last week, those satellites had performed 21 collision avoidance maneuvers autonomously. All of them involved objects on track to make close approaches that were not maneuverable.

However, the Space News article - like many others - missed something Germany's N-TV got

https://disq.us/url?url=https%3A%2F%2Fwww.n-tv.de%2Fwissen%2FEsa-Satellit-umfliegt-SpaceX-Satelliten-article21248848.html%3AC5OqYLrMWdGxRFfVSSMamxubP-c&cuid=3432148

(Google Translate)

Quote
Previously, Esa contacted SpaceX. Together, it was decided that "Aeolus" evades. The agreement is important, said Holger Krag, the head of the Esa Space Attention Office. Otherwise, in the worst case, it could be that both satellites dodge in the same direction and so on. The agreement with SpaceX worked well according to the expert. That's not always the case: "There are satellite operators, they do not react when they write to them."
Title: Re: Starlink : General Discussion - Thread 2
Post by: OTV Booster on 09/21/2019 07:18 pm
The shorter lifetime due to lower orbits would be less of a hit.
If satellite lifespan at 450km is an actual problem you can add years to it by adding 1 kg of krypton to each bird, so 4000kg total upmass.  Quite a bit cheaper than adding an extra layer of satellites.

If routing is a problem you can add hierarchical routing or share the routing load without an extra physical tier.  In any case don't try to simplify software by complexifying hardware unless the software group asks for it.  And then give some thought to what they asked for.  The number of times I asked for cache and got flops and a thermal management problem ... .

They expect the lower sats to have a short lifespan. I think the numbers were ~3-4 years for the low ones and ~5-7 for the high ones. If they’re cheap, de nada.

Ouch. Sounds like the teams weren’t integrated as tight as they might have been. My experience with networking is about 16 years out of date and mostly simple local area stuff. I’m really qualified enough to only have a general idea of routing issues, so take my thoughts and questions as coming from a firm foundation of ignorance. 

On a ground based network ISTM the routing issues would be qualitatively different than StarLink. In either starlink architecture routing would be not just logically but physically dynamic. A ground based router might have several ports but they always physically connect to the same end point and routing is mostly a logical process. starLink has a strong physical routing element so the physical aspect has to be addressed. The two architectures are different ways of addressing this. I’m not so much trying to substitute hardware for software at one point in the system as looking looking at the overall system and thinking about overall system optimization.

In what I propose some things get more difficult but others seem to get easier and probably less expensive. Some of the difficulties have been commented on in ways I understand to one degree or another but honestly, I don’t feel like my understanding of the issues has been expanded very much.

Ce la vie

Phil




Title: Re: Starlink : General Discussion - Thread 2
Post by: allins on 09/21/2019 10:32 pm
Has there been any mention since the May media call of whether Starlink will be sold directly or resold through ISPs?

SpaceX is not in the business of reselling its product thru third parties.

That applies to Musk's other businesses as well.

I very much hope that applies, but has there been any actual evidence to support that claim?  If they do intend to start selling modems next year, then there should be some trace signs of customer support and call center development.  A best effort lead time would be 180-270 days.

The evidence is that there have been no announced marketing deals for Starlink.

No need to make this overly complicated.  Musk will announce it on Twitter with a sign-up/order page on Starlink.com.  They will get a million takers depending on the required deposit, from which they can pick and choose geographies for a beta-ish service.

At first, Starlink customer service can be co-located with Tesla's in Las Vegas.  Built-out in Las Vegas or elsewhere as necessary.
As there is the southern border of Canada to consider in their first iteration of Satellite Service, after 6 launches, do you think that they may utilize Musk's experience with Paypal to enable cross border sign up and payments... Or something similar... or is there some international barrier that I am not aware of?
I'm guessing the CRTC would have to approve a new Internet provider?
Title: Re: Starlink : General Discussion - Thread 2
Post by: DigitalMan on 09/21/2019 11:06 pm
In case it wasn't mentioned before, with the potential close approach to ESA's satellite. That weekend was labor day weekend in the US with the close approach right on labor day, which with the on-call system failure (very commonly used in the software world) there would be literally no person in place who would actually have seen any email. So it's a perfect storm of unfortunate situations (and ESA was still wrong to directly attack SpaceX for it and push that idea in the media).

No SpaceX and ESA are not lacking communication. No SpaceX is not acting incorrectly. They're acting just as well as anyone else in the space industry with regards to space junk, if not better than most. They're just new to the process and their systems aren't operational mode yet which will explain any oversight that takes places.

I found it interesting Starlink performed 21 autonomous avoidance maneuvers to avoid objects that had no propulsion.  Odd that the media isn't talking about it especially since it is a new thing, no?

To be honest, I didn't know that either and I can't find it via google. Got a link?

I think this was already posted here somewhere,

https://twitter.com/jeff_foust/status/1174755098582323200
Title: Re: Starlink : General Discussion - Thread 2
Post by: QuantumG on 09/21/2019 11:51 pm
I imagine SpaceX will need government approval to sell the ground portion (umm.. the antenna?) in every country they want to sell it in. Anyone have a different opinion?
Title: Re: Starlink : General Discussion - Thread 2
Post by: speedevil on 09/22/2019 12:02 am
I imagine SpaceX will need government approval to sell the ground portion (umm.. the antenna?) in every country they want to sell it in. Anyone have a different opinion?
The approvals vary markedly, from just RF licensing, to going through the various hoops for assorted government wiretap requirements.
In regions like China, you're going to run into additional issues with regard to non-local  ownership of ISPs, for example, additionally to any firewall issues.

https://www.whoishostingthis.com/blog/2017/01/02/investigatory-powers-act/ - for example (UK).

It may be that in some cases this can be done in software, if they can prove that they can do this to the satisfaction of the governments involved, other cases might require all traffic to go through a gateway in that country.

It's very much a country by country (and in some cases finer graduations) thing.
Title: Re: Starlink : General Discussion - Thread 2
Post by: QuantumG on 09/22/2019 12:11 am
other cases might require all traffic to go through a gateway in that country.

Shadows of Iridium.
Title: Re: Starlink : General Discussion - Thread 2
Post by: IainMcClatchie on 09/23/2019 10:11 am
Semmel, sorry for jumping in late here, but I noticed some things about the link you gave to SpaceMicro's OISL product page (http://"http://www.spacemicro.com/assets/datasheets/rf-and-microwave/lasercom.pdf").

1) They are using two parallel beam expanders, one for transmit and one for receive.  This makes a lot of sense to me: using a beamsplitter to combine the two paths into a single optic still leaves you with the problem of calibrating the alignment between the two devices to either fork of the beamsplitter.  For calibration you can emit a beam at a diffuse wall at some reasonable distance, and measure what beam offset you receive.  Subtract the stereo angle between the two optics at that distance.

2) The first picture looks like a CAD render of two little Cassegrain telescopes.  The second pictures looks more like a refractor.  Maybe the beam expander is two stages, as getting from 9 microns to 5+ cm is almost 4 orders of magnitude.

3) The tracking appears to be a 4-cell receiver.  I presume this is fine tracking and coarse tracking uses some other method.

4) They are using telecom 1550nm lasers.  I've seen experimental systems with 40 channels of 40 Gb/s each, it seems like these would just swap in if they can be packaged into the power/weight numbers needed.  The power numbers seem suprisingly high (FPGAs doing some kind of FEC?), I suspect that's the limit here.

4b) I'll also note that commercial systems would let you pass some/most DWDM channels from one receiver to another transmitter without ever dropping into the digital domain.  Using add/drop muxes like this, you could have each satellite use just four laser links, but have very near speed-of-light (lowest possible latency) channels to as many as 160 other satellites.  Why bother routing in digital on every hop?  You could probably arrange for most packets to go up, make one routing decision, get routed optically to a destination satellite, back to RF and down.  That would minimize control latency.

5) The gimbal looks like a commercial gimbal which is wholly unsuited for flat-packing into a StarLink Pizza.  But note that they tilt/tip the entire optical train down to a fiber pigtail instead of just a flat mirror.  This makes more sense to me, since high speed tracking is not really necessary.  When targeting a satellite in an adjacent orbital plane, the angle needed will sweep through +/- 20 degrees or so every 90 minutes.

6) A commercial gimbal is probably going to have ball bearings.  These have been problematic on the ISS solar panels (Google Solar Alpha Rotary Joint), and suck for high accuracy pointing because the balls make detents in their races.  The better way in high-accuracy optics is flexure joints, which can last forever, don't need lubricants, and have little hysteresis.  You'd need compound flexure joints to get +/- 20 degrees for zillions of cycles, but that's possible.

Commercial 1550nm SFP+ laser modules are 1.5 watts, and transmit 2 dBm and receive -20 dBm.  This means they need to receive 1% of the power transmitted.  That won't work for OISL.  Here's an off-the-shelf amplifier (http://"https://www.fiberlabs.com/bt_amp_index/c-band-bt-highpower-amp/") that will boost output to +37 dBm (5 watts), but that gets spread across all the DWDM channels.  Note: the amp burns 170 watts.  So if you've got 10 channels, you'd need to keep your loss to 47 dB.  There will be a bunch of other losses in the system, so figure you need 43 dB.

The new StarLink proposal has 22 satellites in a plane, at 550 km altitude.  That's approximately 2000 km between satellites.  Two 16 cm apertures passing 1550 nm light would have 43 dBm loss.

I noticed that the 25 Gb/s per lane transceivers have roughly the same specs: transmit 2.5 dBm and receive -20 dBm.  15 watt (42 dBm) amplifiers can be had.  So probably the upper limit that can be achieved with off the shelf equipment right now is 42 dBm total transmit power spread across 40 channels with 18 cm diameter apertures, giving 1 Tb/s transmit and receive in each of 4 links.  It'll take a lot of RF to keep up with that.
Title: Re: Starlink : General Discussion - Thread 2
Post by: RedLineTrain on 09/23/2019 04:16 pm
Has there been any mention since the May media call of whether Starlink will be sold directly or resold through ISPs?

SpaceX is not in the business of reselling its product thru third parties.

That applies to Musk's other businesses as well.

I very much hope that applies, but has there been any actual evidence to support that claim?  If they do intend to start selling modems next year, then there should be some trace signs of customer support and call center development.  A best effort lead time would be 180-270 days.

The evidence is that there have been no announced marketing deals for Starlink.

No need to make this overly complicated.  Musk will announce it on Twitter with a sign-up/order page on Starlink.com.  They will get a million takers depending on the required deposit, from which they can pick and choose geographies for a beta-ish service.

At first, Starlink customer service can be co-located with Tesla's in Las Vegas.  Built-out in Las Vegas or elsewhere as necessary.
As there is the southern border of Canada to consider in their first iteration of Satellite Service, after 6 launches, do you think that they may utilize Musk's experience with Paypal to enable cross border sign up and payments... Or something similar... or is there some international barrier that I am not aware of?

I don't know of any international barrier other than SpaceX will have to get approved for service in each territory, much as it has with the FCC in the US.  It appears that SpaceX is taking a US-first approach, perhaps because dealing with a single regulatory body for what is a rapidly-evolving constellation design is much easier.

OneWeb is taking the opposite approach by going international from the start and working with local operators.  It's an interesting contrast.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Asteroza on 09/24/2019 01:04 am
The shorter lifetime due to lower orbits would be less of a hit.
If satellite lifespan at 450km is an actual problem you can add years to it by adding 1 kg of krypton to each bird, so 4000kg total upmass.  Quite a bit cheaper than adding an extra layer of satellites.

If routing is a problem you can add hierarchical routing or share the routing load without an extra physical tier.  In any case don't try to simplify software by complexifying hardware unless the software group asks for it.  And then give some thought to what they asked for.  The number of times I asked for cache and got flops and a thermal management problem ... .

They expect the lower sats to have a short lifespan. I think the numbers were ~3-4 years for the low ones and ~5-7 for the high ones. If they’re cheap, de nada.

Ouch. Sounds like the teams weren’t integrated as tight as they might have been. My experience with networking is about 16 years out of date and mostly simple local area stuff. I’m really qualified enough to only have a general idea of routing issues, so take my thoughts and questions as coming from a firm foundation of ignorance. 

On a ground based network ISTM the routing issues would be qualitatively different than StarLink. In either starlink architecture routing would be not just logically but physically dynamic. A ground based router might have several ports but they always physically connect to the same end point and routing is mostly a logical process. starLink has a strong physical routing element so the physical aspect has to be addressed. The two architectures are different ways of addressing this. I’m not so much trying to substitute hardware for software at one point in the system as looking looking at the overall system and thinking about overall system optimization.

In what I propose some things get more difficult but others seem to get easier and probably less expensive. Some of the difficulties have been commented on in ways I understand to one degree or another but honestly, I don’t feel like my understanding of the issues has been expanded very much.

Ce la vie

Phil

In the open world, dynamic meshes with mostly fixed gateway anchors have been largely demonstrated via 802.11s, and things like the BATMAN and ROBIN network routing protocols. Those ostensibly were oriented more towards weird local networks of wifi devices hopping to an internet gateway (think protesters being backhauled by some local coffeeshop wifi).

There are the various 802.15.4 derivative mesh networking setups,such as that used by ZigBee and Thread, though those are more IoT oriented and not heavily dynamic.

There are a number of vector distance based mesh routing protocols that may be more suited for Starlink (such as AODV), but they might also roll their own.
Title: Re: Starlink : General Discussion - Thread 2
Post by: oldAtlas_Eguy on 09/24/2019 01:23 am
Semmel, sorry for jumping in late here, but I noticed some things about the link you gave to SpaceMicro's OISL product page (http://"http://www.spacemicro.com/assets/datasheets/rf-and-microwave/lasercom.pdf").

1) They are using two parallel beam expanders, one for transmit and one for receive.  This makes a lot of sense to me: using a beamsplitter to combine the two paths into a single optic still leaves you with the problem of calibrating the alignment between the two devices to either fork of the beamsplitter.  For calibration you can emit a beam at a diffuse wall at some reasonable distance, and measure what beam offset you receive.  Subtract the stereo angle between the two optics at that distance.

2) The first picture looks like a CAD render of two little Cassegrain telescopes.  The second pictures looks more like a refractor.  Maybe the beam expander is two stages, as getting from 9 microns to 5+ cm is almost 4 orders of magnitude.

3) The tracking appears to be a 4-cell receiver.  I presume this is fine tracking and coarse tracking uses some other method.

4) They are using telecom 1550nm lasers.  I've seen experimental systems with 40 channels of 40 Gb/s each, it seems like these would just swap in if they can be packaged into the power/weight numbers needed.  The power numbers seem suprisingly high (FPGAs doing some kind of FEC?), I suspect that's the limit here.

4b) I'll also note that commercial systems would let you pass some/most DWDM channels from one receiver to another transmitter without ever dropping into the digital domain.  Using add/drop muxes like this, you could have each satellite use just four laser links, but have very near speed-of-light (lowest possible latency) channels to as many as 160 other satellites.  Why bother routing in digital on every hop?  You could probably arrange for most packets to go up, make one routing decision, get routed optically to a destination satellite, back to RF and down.  That would minimize control latency.

5) The gimbal looks like a commercial gimbal which is wholly unsuited for flat-packing into a StarLink Pizza.  But note that they tilt/tip the entire optical train down to a fiber pigtail instead of just a flat mirror.  This makes more sense to me, since high speed tracking is not really necessary.  When targeting a satellite in an adjacent orbital plane, the angle needed will sweep through +/- 20 degrees or so every 90 minutes.

6) A commercial gimbal is probably going to have ball bearings.  These have been problematic on the ISS solar panels (Google Solar Alpha Rotary Joint), and suck for high accuracy pointing because the balls make detents in their races.  The better way in high-accuracy optics is flexure joints, which can last forever, don't need lubricants, and have little hysteresis.  You'd need compound flexure joints to get +/- 20 degrees for zillions of cycles, but that's possible.

Commercial 1550nm SFP+ laser modules are 1.5 watts, and transmit 2 dBm and receive -20 dBm.  This means they need to receive 1% of the power transmitted.  That won't work for OISL.  Here's an off-the-shelf amplifier (http://"https://www.fiberlabs.com/bt_amp_index/c-band-bt-highpower-amp/") that will boost output to +37 dBm (5 watts), but that gets spread across all the DWDM channels.  Note: the amp burns 170 watts.  So if you've got 10 channels, you'd need to keep your loss to 47 dB.  There will be a bunch of other losses in the system, so figure you need 43 dB.

The new StarLink proposal has 22 satellites in a plane, at 550 km altitude.  That's approximately 2000 km between satellites.  Two 16 cm apertures passing 1550 nm light would have 43 dBm loss.

I noticed that the 25 Gb/s per lane transceivers have roughly the same specs: transmit 2.5 dBm and receive -20 dBm.  15 watt (42 dBm) amplifiers can be had.  So probably the upper limit that can be achieved with off the shelf equipment right now is 42 dBm total transmit power spread across 40 channels with 18 cm diameter apertures, giving 1 Tb/s transmit and receive in each of 4 links.  It'll take a lot of RF to keep up with that.

On a set of 72 sats in a ring and an up down rf throughput per sat of 32gbit on these  V1 design, the total possible data traffic on any one link if all data is routed from a sat to some other sat to be as high as .5Tbit. But is likely to be much less. Until the rf link data throughput increases in the V2 heavier sat with 64 or even 256Gbit.

Because of aggregate loading even on a set of sats with 256Gbit throughput a 1Tbit link should work fine. Loading of 20% of the total rf capability of a set of sats is considered a high value and likely unreachable. Using a 2X of rf throughput for sizing of thr optical link should keep you from having significant packet traffic jams.
Title: Re: Starlink : General Discussion - Thread 2
Post by: DistantTemple on 09/25/2019 01:19 am
https://www.marieclaire.com/celebrity/a28967312/women-changing-future/
Quote from: Gwynne Shotwell in Marie Claire - 25 Women Changing the future
Eventually, we’ll expand this to connect people around and between other heavenly bodies.
This is a vision for 2044. It has repeatedly come up whether Starlink will connect to Mars etc. This doesn't prove it will be attempted straight away, but it shows intent.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Rondaz on 09/28/2019 12:48 pm
Interesting new filing by SpaceX on first to launch issues for NGSO systems characterizing opponents as "Non-US Operators" whereas SpaceX is the "Truly American Operator". Clearly the intention is to simply ignore ITU priority in favor of "America first"

https://twitter.com/TMFAssociates/status/1177636294748278784
Title: Re: Starlink : General Discussion - Thread 2
Post by: Rondaz on 09/28/2019 12:48 pm
To be explicit, SpaceX believe they can ignore ITU filing order since the rules don't grant any "permanent priority" to earlier filed systems, due to WRC-03 Res. 2 (see http://search.itu.int/history/HistoryDigitalCollectionDocLibrary/4.127.43.en.100.pdf …), which ITU lawyers regard as an aspirational & irrelevant historical curiosity..

https://twitter.com/TMFAssociates/status/1177655559639580677
Title: Re: Starlink : General Discussion - Thread 2
Post by: vsatman on 10/01/2019 04:05 pm
I mean this news may be interesting - 10 minutes ago I received mail:
//Dear valued LeoSat Partner,  We very much appreciate your interest and commitment to LeoSat and with this letter I would like to update you on the latest developments.
LeoSat as a NewSpace company is confronted with the same challenges of any start-up that is moving along the evolution from vision to reality. Whilst the company maintains its strong vision as a unique solution for B2B data connectivity in LEO, validated by the market and our early investors, we are now facing critical funding issues.  Late last week we had to make the very difficult decision to cancel our early obtained FCC license that required a long term financial commitment equal to that of multiple FTEs. As a startup we could no longer justify carrying the cost this early in the project and we will reapply for this license closer to launch, in parallel to obtaining our licenses in other countries.
//

Starlink will have minus one competitor  and more interest from investors
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 10/01/2019 06:54 pm
I mean this news may be interesting - 10 minutes ago I received mail:

Not sure if Leosat is completely dead yet, but they're struggling.  I made my reply in a different thread:
https://forum.nasaspaceflight.com/index.php?topic=41647.msg2000288#msg2000288
Title: Re: Starlink : General Discussion - Thread 2
Post by: jak Kennedy on 10/01/2019 07:59 pm

5) The gimbal looks like a commercial gimbal which is wholly unsuited for flat-packing into a StarLink Pizza.  But note that they tilt/tip the entire optical train down to a fiber pigtail instead of just a flat mirror.  This makes more sense to me, since high speed tracking is not really necessary.  When targeting a satellite in an adjacent orbital plane, the angle needed will sweep through +/- 20 degrees or so every 90 minutes.

6) A commercial gimbal is probably going to have ball bearings.  These have been problematic on the ISS solar panels (Google Solar Alpha Rotary Joint), and suck for high accuracy pointing because the balls make detents in their races.  The better way in high-accuracy optics is flexure joints, which can last forever, don't need lubricants, and have little hysteresis.  You'd need compound flexure joints to get +/- 20 degrees for zillions of cycles, but that's possible.

Here is a link to a youtube video re flexable joints starting with a titanium compound hinge for space solar panels and then for thrusters.

https://youtu.be/97t7Xj_iBv0?t=461
Title: Re: Starlink : General Discussion - Thread 2
Post by: vsatman on 10/02/2019 07:47 am
I imagine SpaceX will need government approval to sell the ground portion (umm.. the antenna?) in every country they want to sell it in. Anyone have a different opinion?
Here are 2 different issue
1) Business  or Right to Sell Service/Make Business
  In Mostly countries you have to have  local company for it (some times plus special License) for it..
2) State Security - Police system for control traffic from local citizens . Theoretically provider can route traffic from its Gateway in USA to local Police ,  but  standard decision is local gateway . And all traffic from satellite which crossed in this time  territory this country must be routed via this local Gateway (see Iridium in Russia)
Title: Re: Starlink : General Discussion - Thread 2
Post by: Rondaz on 10/02/2019 02:22 pm
In contrast to @OneWeb and @SpaceX @amazon's @FCC filings for #ProjectKuiper (📄 http://licensing.fcc.gov/cgi-bin/ws.exe/prod/ib/forms/reports/swr031b.hts?q_set=V_SITE_ANTENNA_FREQ.file_numberC/File+Number/%3D/SATLOA2019070400057&prepare=&column=V_SITE_ANTENNA_FREQ.file_numberC/File+Number …) so far only cover Ka band frequencies from 17.7-30.0GHz (see below table).

https://twitter.com/Megaconstellati/status/1179400375314653184
Title: Re: Starlink : General Discussion - Thread 2
Post by: watermod on 10/08/2019 02:05 pm
I can't help but think that the government has CALEA problems with StarLink.
https://www.eff.org/issues/calea (https://www.eff.org/issues/calea)
Title: Re: Starlink : General Discussion - Thread 2
Post by: LiamS on 10/11/2019 09:32 am
This was posted on reddit by user 'not_even_twice' https://www.reddit.com/r/Starlink/comments/dgc1t6/spacex_quietly_files_for_30000_more_satellites/ (https://www.reddit.com/r/Starlink/comments/dgc1t6/spacex_quietly_files_for_30000_more_satellites/)

Quote
On October 7th, the FCC made 20 new, independent filings on behalf of SpaceX. They comprise 30,000 new satellites as broken down below:

1500 sats at 97.7°, 580 km
1500 sats at 85°, 539.7 km
1500 sats at 80°, 532 km
1500 sats at 75°, 524.7 km
1500 sats at 70°, 517.8 km
4500 sats at 53°, 498.8 km
4500 sats at 40°, 488.4 km
4500 sats at 30°, 482.8 km
3000 sats at 53°, 345.6 km
3000 sats at 40°, 334.4 km
3000 sats at 30°, 328.3 km

Source: https://www.itu.int/ITU-R/space/asreceived/Publication/AsReceived

The filings starting with "USASAT-NGSO-3" all come with a letter from the FCC stating "The operating agency for the network is Space Exploration Technologies Corp."

I had a look at the link and it seems to check out. Starship development must be going better than expected.
Title: Re: Starlink : General Discussion - Thread 2
Post by: HeartofGold2030 on 10/11/2019 09:35 am
This was posted on reddit by user 'not_even_twice' https://www.reddit.com/r/Starlink/comments/dgc1t6/spacex_quietly_files_for_30000_more_satellites/ (https://www.reddit.com/r/Starlink/comments/dgc1t6/spacex_quietly_files_for_30000_more_satellites/)

Quote
On October 7th, the FCC made 20 new, independent filings on behalf of SpaceX. They comprise 30,000 new satellites as broken down below:

1500 sats at 97.7°, 580 km
1500 sats at 85°, 539.7 km
1500 sats at 80°, 532 km
1500 sats at 75°, 524.7 km
1500 sats at 70°, 517.8 km
4500 sats at 53°, 498.8 km
4500 sats at 40°, 488.4 km
4500 sats at 30°, 482.8 km
3000 sats at 53°, 345.6 km
3000 sats at 40°, 334.4 km
3000 sats at 30°, 328.3 km

Source: https://www.itu.int/ITU-R/space/asreceived/Publication/AsReceived

The filings starting with "USASAT-NGSO-3" all come with a letter from the FCC stating "The operating agency for the network is Space Exploration Technologies Corp."

I had a look at the link and it seems to check out. Starship development must be going better than expected.

I’m pretty sure this is going to set off some alarm bells in the wider space community, if it gets approved that is...
Title: Re: Starlink : General Discussion - Thread 2
Post by: LiamS on 10/11/2019 09:40 am

I’m pretty sure this is going to set off some alarm bells in the wider space community, if it gets approved that is...

Can't help but agree, I'm a massive advocate of something like starlink and it is setting off my alarm bells.
Title: Re: Starlink : General Discussion - Thread 2
Post by: HeartofGold2030 on 10/11/2019 09:58 am

I’m pretty sure this is going to set off some alarm bells in the wider space community, if it gets approved that is...

Can't help but agree, I'm a massive advocate of something like starlink and it is setting off my alarm bells.

I can already hear the sounds of the lawyers belonging to NASA, ESA, the other constellation providers, astronomy organisations and space debris prevention advocates sharpening their knives...
Title: Re: Starlink : General Discussion - Thread 2
Post by: su27k on 10/11/2019 10:10 am

I’m pretty sure this is going to set off some alarm bells in the wider space community, if it gets approved that is...

Can't help but agree, I'm a massive advocate of something like starlink and it is setting off my alarm bells.

I can already hear the sounds of the lawyers belonging to NASA, ESA, the other constellation providers, astronomy organisations and space debris prevention advocates sharpening their knives...

And they have no case as long as SpaceX follows the rules.

NASA: We have just witnessed how SpaceX and NASA can work out their differences peacefully.

ESA: They have no skin in the game, despite their tweet. They got what, a single satellite in the neighborhood?

Other constellation providers: And what are they going to complaint about, SpaceX is too successful in reusability?

Astronomy organisations: SpaceX already have agreement in place with radio astronomers. And they're working with optical astronomers, I doubt they would have taken this action without mitigation in place.

Space debris prevention: These are low and very low LEO orbits where debris will decay quickly, it's better to have more satellites here than the 1,000km orbits.
Title: Re: Starlink : General Discussion - Thread 2
Post by: GWR64 on 10/11/2019 12:23 pm
This was posted on reddit by user 'not_even_twice' https://www.reddit.com/r/Starlink/comments/dgc1t6/spacex_quietly_files_for_30000_more_satellites/ (https://www.reddit.com/r/Starlink/comments/dgc1t6/spacex_quietly_files_for_30000_more_satellites/)

Quote
On October 7th, the FCC made 20 new, independent filings on behalf of SpaceX. They comprise 30,000 new satellites as broken down below:

1500 sats at 97.7°, 580 km
1500 sats at 85°, 539.7 km
1500 sats at 80°, 532 km
1500 sats at 75°, 524.7 km
1500 sats at 70°, 517.8 km
4500 sats at 53°, 498.8 km
4500 sats at 40°, 488.4 km
4500 sats at 30°, 482.8 km
3000 sats at 53°, 345.6 km
3000 sats at 40°, 334.4 km
3000 sats at 30°, 328.3 km

Source: https://www.itu.int/ITU-R/space/asreceived/Publication/AsReceived

The filings starting with "USASAT-NGSO-3" all come with a letter from the FCC stating "The operating agency for the network is Space Exploration Technologies Corp."

I had a look at the link and it seems to check out. Starship development must be going better than expected.

I’m pretty sure this is going to set off some alarm bells in the wider space community, if it gets approved that is...

Approval for 30,000 satellites in one constellation, who can that approve on our earth?
Title: Re: Starlink : General Discussion - Thread 2
Post by: envy887 on 10/11/2019 12:26 pm
This was posted on reddit by user 'not_even_twice' https://www.reddit.com/r/Starlink/comments/dgc1t6/spacex_quietly_files_for_30000_more_satellites/ (https://www.reddit.com/r/Starlink/comments/dgc1t6/spacex_quietly_files_for_30000_more_satellites/)

Quote
On October 7th, the FCC made 20 new, independent filings on behalf of SpaceX. They comprise 30,000 new satellites as broken down below:

1500 sats at 97.7°, 580 km
1500 sats at 85°, 539.7 km
1500 sats at 80°, 532 km
1500 sats at 75°, 524.7 km
1500 sats at 70°, 517.8 km
4500 sats at 53°, 498.8 km
4500 sats at 40°, 488.4 km
4500 sats at 30°, 482.8 km
3000 sats at 53°, 345.6 km
3000 sats at 40°, 334.4 km
3000 sats at 30°, 328.3 km

Source: https://www.itu.int/ITU-R/space/asreceived/Publication/AsReceived

The filings starting with "USASAT-NGSO-3" all come with a letter from the FCC stating "The operating agency for the network is Space Exploration Technologies Corp."

I had a look at the link and it seems to check out. Starship development must be going better than expected.

I’m pretty sure this is going to set off some alarm bells in the wider space community, if it gets approved that is...

Approval for 30,000 satellites in one constellation, who can that approve on our earth?

It's just approval for radio spectrum use, by a certain number of satellites in certain particular orbits. By international agreement, the ITU handles this.
Title: Re: Starlink : General Discussion - Thread 2
Post by: GWR64 on 10/11/2019 12:51 pm
Hmm, frequency rights globally (who comes first has the rights?), or for specific countries?
Collision risk is not rated? Also for the manned space flight.
If China want to start its own constellation with 100,000 LEO sats in another (free) frequency range, would they get the permission?
Title: Re: Starlink : General Discussion - Thread 2
Post by: RedLineTrain on 10/11/2019 01:18 pm
This is not very many satellites.  Starship will hardly break a sweat.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 10/11/2019 02:02 pm
I wouldn't assume that SpaceX actually intends to launch 30k more satellites.  They may just be filing extra orbits to give themselves more flexibility for future deployments.
Title: Re: Starlink : General Discussion - Thread 2
Post by: niwax on 10/11/2019 02:49 pm
I wouldn't assume that SpaceX actually intends to launch 30k more satellites.  They may just be filing extra orbits to give themselves more flexibility for future deployments.

What are the error margins on these filings? At 5° and 10-20km between planes and thousands of satellites each, they're not far off having an effective worldwide monopoly on those frequencies. It's practically impossible to have another satellite at the same frequency not interfere.
Title: Re: Starlink : General Discussion - Thread 2
Post by: woods170 on 10/11/2019 04:44 pm
I wouldn't assume that SpaceX actually intends to launch 30k more satellites.  They may just be filing extra orbits to give themselves more flexibility for future deployments.

Keyword is successive, not simultaneously.
Title: Re: Starlink : General Discussion - Thread 2
Post by: ZachF on 10/11/2019 05:27 pm
30,000?!?

Not gonna lie, that made me giggle.


The thing is, Starship could easily handle this, even if the satellites grow in mass to well over a tonne.

I think this is also partly a shot across the bow to satellite services and launch providers that the expendable paradigm is over... That Starship isn't just 'a little bit' better than current offerings, but the others are co.pletely obsolete.
Title: Re: Starlink : General Discussion - Thread 2
Post by: rsdavis9 on 10/11/2019 05:34 pm
30,000?!?

Not gonna lie, that made me giggle.


The thing is, Starship could easily handle this, even if the satellites grow in mass to well over a tonne.

I think this is also partly a shot across the bow to satellite services and launch providers that the expendable paradigm is over... That Starship isn't just 'a little bit' better than current offerings, but the others are co.pletely obsolete.

Interesting that we are moving towards reusable rockets and expendable satellites. Complete reversal.
Title: Re: Starlink : General Discussion - Thread 2
Post by: su27k on 10/11/2019 05:48 pm
I wouldn't assume that SpaceX actually intends to launch 30k more satellites.  They may just be filing extra orbits to give themselves more flexibility for future deployments.

Keyword is successive, not simultaneously.

What does successive mean in this context? ITU approval has a time limit (6 years?), if they don't use it within the time limit they'll lose it. So they can't file now for an orbit that they won't use for another 10 years for example.
Title: Re: Starlink : General Discussion - Thread 2
Post by: docmordrid on 10/11/2019 06:24 pm
I wouldn't assume that SpaceX actually intends to launch 30k more satellites.  They may just be filing extra orbits to give themselves more flexibility for future deployments.

Keyword is successive, not simultaneously.

What does successive mean in this context? ITU approval has a time limit (6 years?), if they don't use it within the time limit they'll lose it. So they can't file now for an orbit that they won't use for another 10 years for example.

If each satellite in the constellation needs replacing every 5 years, plus accounting for a non-zero failure rate, they may need 30,000 birds a lot sooner than first-blush impressions indicate.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Cheapchips on 10/11/2019 07:21 pm
Interesting that we are moving towards reusable rockets and expendable satellites. Complete reversal.

There must be a point where expending satellites transitions into retrieving and reusing them.
Title: Re: Starlink : General Discussion - Thread 2
Post by: rsdavis9 on 10/11/2019 07:54 pm
Interesting that we are moving towards reusable rockets and expendable satellites. Complete reversal.

There must be a point where expending satellites transitions into retrieving and reusing them.

As technology change accelerates it will be easier to build new ones and let the old ones dispose on reentry. If the technology for low earth constellations advances and plateaus then letting them stay up longer will to be better.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Robotbeat on 10/12/2019 04:09 am
To be explicit, SpaceX believe they can ignore ITU filing order since the rules don't grant any "permanent priority" to earlier filed systems, due to WRC-03 Res. 2 (see http://search.itu.int/history/HistoryDigitalCollectionDocLibrary/4.127.43.en.100.pdf …), which ITU lawyers regard as an aspirational & irrelevant historical curiosity..

https://twitter.com/TMFAssociates/status/1177655559639580677
It's worth noting, again, that this guy is regularly a Starlink (and SpaceX) skeptic. So take it with a grain of salt. (Doesn't mean he's wrong, but it's pretty clear he's got a spin, here.)
Title: Re: Starlink : General Discussion - Thread 2
Post by: meekGee on 10/12/2019 04:14 am
Interesting that we are moving towards reusable rockets and expendable satellites. Complete reversal.

There must be a point where expending satellites transitions into retrieving and reusing them.
Entropy begs to disagree...

Once that pack of satellites leaves the dispenser and disperses, it becomes hugely difficult to go chase and retrieve them.  Better to let them disperse even further, into their constituent molecules...
Title: Re: Starlink : General Discussion - Thread 2
Post by: Zed_Noir on 10/12/2019 04:57 am
Interesting that we are moving towards reusable rockets and expendable satellites. Complete reversal.

There must be a point where expending satellites transitions into retrieving and reusing them.
Entropy begs to disagree...

Once that pack of satellites leaves the dispenser and disperses, it becomes hugely difficult to go chase and retrieve them.  Better to let them disperse even further, into their constituent molecules...

Maybe with enough onboard Delta-V, later Starlink satellites that have finish their planned service life can assemble in one location for pickup by a Starship. The retrieved Starlink satellites can be recycled for later flights with updated modular components as needed.

P.S. minor nit. What Starlink dispenser?  :P  The Starlink flatpack stack is directly attached to the payload adapter.
Title: Re: Starlink : General Discussion - Thread 2
Post by: ncb1397 on 10/12/2019 05:38 am

P.S. minor nit. What Starlink dispenser?  :P  The Starlink flatpack stack is directly attached to the payload adapter.

What is the silvery beam? There also seems to be greenish connector rings and some structure underneath that isn't standard payload adapter ring. It appears that SpaceX cut the video when the actual deployment sequence was initiated and afterwards stuff like the connector rings were gone. It would have been nice to understand how they go from rigid structure to disconnected, but that appears to be closely gaurded.
Title: Re: Starlink : General Discussion - Thread 2
Post by: meekGee on 10/12/2019 12:24 pm
Interesting that we are moving towards reusable rockets and expendable satellites. Complete reversal.

There must be a point where expending satellites transitions into retrieving and reusing them.
Entropy begs to disagree...

Once that pack of satellites leaves the dispenser and disperses, it becomes hugely difficult to go chase and retrieve them.  Better to let them disperse even further, into their constituent molecules...

Maybe with enough onboard Delta-V, later Starlink satellites that have finish their planned service life can assemble in one location for pickup by a Starship. The retrieved Starlink satellites can be recycled for later flights with updated modular components as needed.

P.S. minor nit. What Starlink dispenser?    The Starlink flatpack stack is directly attached to the payload adapter.
My 60" TV is looking old and small. If only there was a convenient way to incinerate it when I get a new 80" one.  That's the analogy you're looking for.

And dispenser, yes - the payload adapter or second stage or Starship, it doesn't matter.  That point in time when all satellites were packed, organized, and had the same orbit. 2nd law says it's hard to put Humpty back together again.
Title: Re: Starlink : General Discussion - Thread 2
Post by: DistantTemple on 10/12/2019 12:49 pm
Interesting that we are moving towards reusable rockets and expendable satellites. Complete reversal.

There must be a point where expending satellites transitions into retrieving and reusing them.
Entropy begs to disagree...

Once that pack of satellites leaves the dispenser and disperses, it becomes hugely difficult to go chase and retrieve them.  Better to let them disperse even further, into their constituent molecules...

Maybe with enough onboard Delta-V, later Starlink satellites that have finish their planned service life can assemble in one location for pickup by a Starship. The retrieved Starlink satellites can be recycled for later flights with updated modular components as needed.

P.S. minor nit. What Starlink dispenser?    The Starlink flatpack stack is directly attached to the payload adapter.
My 60" TV is looking old and small. If only there was a convenient way to incinerate it when I get a new 80" one.  That's the analogy you're looking for.

And dispenser, yes - the payload adapter or second stage or Starship, it doesn't matter.  That point in time when all satellites were packed, organized, and had the same orbit. 2nd law says it's hard to put Humpty back together again.
Factory automation systems easily rotate randomly orientated parts, and place them in a carrier or dispenser. An energy or intelligence input overrides entropy. Also releasing satellites to manoeuvre to planned orbits is not increasing entropy!
This may not be pressing for SX in such a low orbit, but for the large constellations in higher orbits that decay more slowly it may well become a useful method in a few years, not so much for recycling, but for reliably clearing end of mission sats from earth orbit. Reserving propellant for manoeuvring to a "pick up orbit" may be a cost effectiveway to guarantee end of mission removal. Another use of SS!
Title: Re: Starlink : General Discussion - Thread 2
Post by: rsdavis9 on 10/12/2019 01:09 pm
Not sure if the correct thread.

One use of a 10,000's of satellite network. How about a large radio telescope? They will have precise positions from their orbit calc requirements. The positions will only get better with the addition of laser inter-satellite links. Combining the signals from half of a sphere of receivers should give excellent sensitivity and spatial resolution.
   
Title: Re: Starlink : General Discussion - Thread 2
Post by: Jcc on 10/12/2019 01:44 pm
Not sure if the correct thread.

One use of a 10,000's of satellite network. How about a large radio telescope? They will have precise positions from their orbit calc requirements. The positions will only get better with the addition of laser inter-satellite links. Combining the signals from half of a sphere of receivers should give excellent sensitivity and spatial resolution.
 

Combined use would be rough, Starlink generates a lot of radio signal, and LEO is not ideal for a radio telescope. But a cheap dedicated radio telescope satellite that can be produced and launched to high orbit in large numbers would be interesting.
Title: Re: Starlink : General Discussion - Thread 2
Post by: su27k on 10/12/2019 01:56 pm
Interesting that we are moving towards reusable rockets and expendable satellites. Complete reversal.

There must be a point where expending satellites transitions into retrieving and reusing them.
Entropy begs to disagree...

Once that pack of satellites leaves the dispenser and disperses, it becomes hugely difficult to go chase and retrieve them.  Better to let them disperse even further, into their constituent molecules...

Maybe with enough onboard Delta-V, later Starlink satellites that have finish their planned service life can assemble in one location for pickup by a Starship. The retrieved Starlink satellites can be recycled for later flights with updated modular components as needed.

P.S. minor nit. What Starlink dispenser?    The Starlink flatpack stack is directly attached to the payload adapter.
My 60" TV is looking old and small. If only there was a convenient way to incinerate it when I get a new 80" one.  That's the analogy you're looking for.

A better analog may be companies replacing their laptops and desktops after a few years. Although the replaced hardware don't usually get incinerated, they end up on ebay or other places where they can continue to contribute value. Not sure if 2nd hand Starlink would work though, given the proprietary nature and liability involved.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 10/12/2019 03:01 pm
Not sure if the correct thread.

One use of a 10,000's of satellite network. How about a large radio telescope? They will have precise positions from their orbit calc requirements. The positions will only get better with the addition of laser inter-satellite links. Combining the signals from half of a sphere of receivers should give excellent sensitivity and spatial resolution.
 

If you want to discuss this please make a separate thread for it.  It really doesn't have anything to do with the current Starlink constellation.
Title: Re: Starlink : General Discussion - Thread 2
Post by: matthewkantar on 10/12/2019 03:37 pm

P.S. minor nit. What Starlink dispenser?  :P  The Starlink flatpack stack is directly attached to the payload adapter.

What is the silvery beam? There also seems to be greenish connector rings and some structure underneath that isn't standard payload adapter ring. It appears that SpaceX cut the video when the actual deployment sequence was initiated and afterwards stuff like the connector rings were gone. It would have been nice to understand how they go from rigid structure to disconnected, but that appears to be closely gaurded.

My guess is that the “beam” is like a seat belt or tape measure, retracts into the payload adapter.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 10/12/2019 04:11 pm

P.S. minor nit. What Starlink dispenser?  :P  The Starlink flatpack stack is directly attached to the payload adapter.

What is the silvery beam? There also seems to be greenish connector rings and some structure underneath that isn't standard payload adapter ring. It appears that SpaceX cut the video when the actual deployment sequence was initiated and afterwards stuff like the connector rings were gone. It would have been nice to understand how they go from rigid structure to disconnected, but that appears to be closely gaurded.

My guess is that the “beam” is like a seat belt or tape measure, retracts into the payload adapter.

There are four debris objects associated with that launch.
Title: Re: Starlink : General Discussion - Thread 2
Post by: ncb1397 on 10/12/2019 07:46 pm

P.S. minor nit. What Starlink dispenser?  :P  The Starlink flatpack stack is directly attached to the payload adapter.

What is the silvery beam? There also seems to be greenish connector rings and some structure underneath that isn't standard payload adapter ring. It appears that SpaceX cut the video when the actual deployment sequence was initiated and afterwards stuff like the connector rings were gone. It would have been nice to understand how they go from rigid structure to disconnected, but that appears to be closely gaurded.

My guess is that the “beam” is like a seat belt or tape measure, retracts into the payload adapter.

There are four debris objects associated with that launch.

They all have RCS signatures of between 1 square meter and .1 square meters. So,it would be consistent with a 10 meter long .1 meter wide beam. The rings alone wouldn't be in that size range.
Title: Re: Starlink : General Discussion - Thread 2
Post by: vsatman on 10/12/2019 09:28 pm
//On October 7th, the FCC made 20 new, independent filings on behalf of SpaceX. They comprise 30,000 new satellites...
I mean its mostly frequency coordination  question in future negotions between Space X  and/or  OneWEb /TeleSat, who have FCC license for USA market and Nothing with really launch  this sats..

ITU will send this files to other member  some of them (Gonduras or Costa Rica who don`t have own LEO constellation)  will say  YES!!! (and Starlink can use its frequency in those country) , but  another ( for example Russia or China)   will say definitiv NO..
and under Russian  or China`s territory   Space X  has to switch off  all transmitters  on Starlink`s sats 
Title: Re: Starlink : General Discussion - Thread 2
Post by: Rondaz on 10/13/2019 08:06 pm
Would like to believe this #satellite constellation from @spacex is even remotely realistic. The challenges of building the ground infrastructure is even bigger than the incredible challenge of building the constellation.

https://twitter.com/Den_is_Social/status/1183431278814748672
Title: Re: Starlink : General Discussion - Thread 2
Post by: Draggendrop on 10/13/2019 08:46 pm
Would like to believe this #satellite constellation from @spacex is even remotely realistic. The challenges of building the ground infrastructure is even bigger than the incredible challenge of building the constellation.

https://twitter.com/Den_is_Social/status/1183431278814748672

-----------------------
That would be his opinion...mine differs.

A cost effective consumer interface is the challenge and I have confidence in their abilities.

They are not throwing stuff into orbit on a whim...they have an evolving plan and I'll wait it out with patience.

just my 2 cents.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 10/13/2019 09:05 pm
Has anyone looked through the new ITU filings to see what frequencies they're using?  I wonder if they're all Ku/Ka.  I really don't feel like poking through all of those, maybe I'll get around to it some day.  The only one I opened was Ku/Ka.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 10/13/2019 11:12 pm
Has anyone looked through the new ITU filings to see what frequencies they're using?  I wonder if they're all Ku/Ka.  I really don't feel like poking through all of those, maybe I'll get around to it some day.  The only one I opened was Ku/Ka.

They do seem to be Ku/Ka.  SpaceX has suggested the FCC start another processing round for Kuiper (and OneWeb's modification to increase their constellation size).  I wonder if when another processing round does get started, whether SpaceX will try to add Ku/Ka to their VLEO sats, much like they added V-band to their original 4000 Ku/Ka-band sats.
Title: Re: Starlink : General Discussion - Thread 2
Post by: su27k on 10/16/2019 05:15 am
Official SpaceX statement regarding the 30,000 satellites filing: https://spacenews.com/spacex-submits-paperwork-for-30000-more-starlink-satellites/

Quote
“As demand escalates for fast, reliable internet around the world, especially for those where connectivity is non-existent, too expensive or unreliable, SpaceX is taking steps to responsibly scale Starlink’s total network capacity and data density to meet the growth in users’ anticipated needs.”
Title: Re: Starlink : General Discussion - Thread 2
Post by: CJ on 10/16/2019 05:30 am
Official SpaceX statement regarding the 30,000 satellites filing: https://spacenews.com/spacex-submits-paperwork-for-30000-more-starlink-satellites/

Quote
“As demand escalates for fast, reliable internet around the world, especially for those where connectivity is non-existent, too expensive or unreliable, SpaceX is taking steps to responsibly scale Starlink’s total network capacity and data density to meet the growth in users’ anticipated needs.”

30,000! Um, that's ambitious to say the least, given that the total number of satellites launched since Sputnik is around 9000.

On the other hand... assuming Starship Cargo works, SpaceX, and SpaceX alone, will have the launch capacity to pull it off. No one else will.

Title: Re: Starlink : General Discussion - Thread 2
Post by: docmordrid on 10/16/2019 06:29 am
Official SpaceX statement regarding the 30,000 satellites filing: https://spacenews.com/spacex-submits-paperwork-for-30000-more-starlink-satellites/

Quote
“As demand escalates for fast, reliable internet around the world, especially for those where connectivity is non-existent, too expensive or unreliable, SpaceX is taking steps to responsibly scale Starlink’s total network capacity and data density to meet the growth in users’ anticipated needs.”

30,000! Um, that's ambitious to say the least, given that the total number of satellites launched since Sputnik is around 9000.

On the other hand... assuming Starship Cargo works, SpaceX, and SpaceX alone, will have the launch capacity to pull it off. No one else will.

I'm not sure if this is a high bid to make what they'll settle for/really want more palatable to ITU, if its to warn off big talkers who don't  frequencies or real hardware yet, or both.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Asteroza on 10/16/2019 06:42 am
Jeez, at this rate how long before Elon brings back the white kitty, puts on a grey suit, raises his pinky finger and says

"1 MILLION satellites..."

while pressuring the ITU?
Title: Re: Starlink : General Discussion - Thread 2
Post by: Cheapchips on 10/16/2019 08:10 am
What surprises me, as someone who knows nothing, is that they haven't chosen to scale with larger, more capable satellites.

Easier disposal with the current size?  Better economics of scale for manufacturing? Easier deployment? Better fairing packing?
Title: Re: Starlink : General Discussion - Thread 2
Post by: dondar on 10/16/2019 08:29 am
It's always fun to see "broken telephone" in action.



The technological difficulties  in building ground infrastructure are are a priori easier manageable and are much easier to solve than space tech. And yes, it's very easy to notice that SpaceX do collect necessary people and do develop all necessary parts of the ground infrastructure starting with terminals/software and ending with financial/administrative management appendix.

The "deadly" challenges to build ground infrastructure lie primarily in the regulatory realm.

I don't believe China, Russia, India, Brasil will allow use of spacelink terminals without constructing some regional corporations to control traffic and be involved in financial flows.
Hence "USA FIRST."
Title: Re: Starlink : General Discussion - Thread 2
Post by: Galactic Penguin SST on 10/16/2019 11:54 am
In other news:

https://twitter.com/Astro_Jonny/status/1184422813001768960

Does this really help to reduce the optical magnitude and flares at all?  :-\
Title: Re: Starlink : General Discussion - Thread 2
Post by: Cheapchips on 10/16/2019 12:33 pm
In other news:

https://twitter.com/Astro_Jonny/status/1184422813001768960

Does this really help to reduce the optical magnitude and flares at all?  :-\

Well, there's always Vantablack, if that's hardy enough for space.
Title: Re: Starlink : General Discussion - Thread 2
Post by: rsdavis9 on 10/16/2019 02:22 pm
To lessen the startlink magnitude:
Paint the earth facing black.
The solar panels should always be facing the sun so should not be a problem. The narrow band where the earth is in shadow and the satellites are in the sun, you just have to be careful and make sure the panels are "aimed" away from earth at a slight angle for their reflection.
Title: Re: Starlink : General Discussion - Thread 2
Post by: su27k on 10/16/2019 03:13 pm
In other news:

https://twitter.com/Astro_Jonny/status/1184422813001768960

Does this really help to reduce the optical magnitude and flares at all?  :-\

We'll know in a month, won't we...

What surprises me, as someone who knows nothing, is that they haven't chosen to scale with larger, more capable satellites.

Easier disposal with the current size?  Better economics of scale for manufacturing? Easier deployment? Better fairing packing?

The first two seem to be big ones. Also more satellites means it's easier for a user on the ground to lock on to a satellite with a favorable angle.
Title: Re: Starlink : General Discussion - Thread 2
Post by: envy887 on 10/16/2019 03:29 pm
In other news:

https://twitter.com/Astro_Jonny/status/1184422813001768960

Does this really help to reduce the optical magnitude and flares at all?  :-\

If by "bottom" they mean "all surfaces with a view of Earth", then yes, but that sounds pretty hard.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Yggdrasill on 10/16/2019 06:21 pm
I think they would get pretty close to covering all surfaces with a view of earth by covering the "bottom":

(https://image.businessinsider.com/5d6e862c2e22af14f94ccbb6?width=1300&format=jpeg&auto=webp)
Title: Re: Starlink : General Discussion - Thread 2
Post by: Barley on 10/16/2019 06:46 pm
What surprises me, as someone who knows nothing, is that they haven't chosen to scale with larger, more capable satellites.

Easier disposal with the current size?  Better economics of scale for manufacturing? Easier deployment? Better fairing packing?
Smaller satellites are more flexible if the market is smaller or takes longer to develop than expected.  Deploying more satellites allows planning for outrageous success without taking an additional huge gamble.  No matter what the technical merits, you have to remain solvent.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Ludus on 10/16/2019 07:03 pm
What surprises me, as someone who knows nothing, is that they haven't chosen to scale with larger, more capable satellites.

Easier disposal with the current size?  Better economics of scale for manufacturing? Easier deployment? Better fairing packing?

The current design is intended to deploy on F9 and is pretty near the limits of their capabilities to launch a working constellation at this size. Once they transition to Starship they can apply what they’ve learned as well as just scaling up the size of satellites. As long as they keep them backward compatible they can start that any time they’re ready.
Title: Re: Starlink : General Discussion - Thread 2
Post by: envy887 on 10/16/2019 07:21 pm
I think they would get pretty close to covering all surfaces with a view of earth by covering the "bottom":

(https://image.businessinsider.com/5d6e862c2e22af14f94ccbb6?width=1300&format=jpeg&auto=webp)

Dunno, it looks to me like every point on the extended solar panel has a view of Earth. Can't paint that black.
Title: Re: Starlink : General Discussion - Thread 2
Post by: woods170 on 10/16/2019 07:24 pm
I wouldn't assume that SpaceX actually intends to launch 30k more satellites.  They may just be filing extra orbits to give themselves more flexibility for future deployments.

Keyword is successive, not simultaneously.

What does successive mean in this context? ITU approval has a time limit (6 years?), if they don't use it within the time limit they'll lose it. So they can't file now for an orbit that they won't use for another 10 years for example.

If each satellite in the constellation needs replacing every 5 years, plus accounting for a non-zero failure rate, they may need 30,000 birds a lot sooner than first-blush impressions indicate

This.
Title: Re: Starlink : General Discussion - Thread 2
Post by: ZachF on 10/16/2019 11:47 pm
I think they would get pretty close to covering all surfaces with a view of earth by covering the "bottom":

(https://image.businessinsider.com/5d6e862c2e22af14f94ccbb6?width=1300&format=jpeg&auto=webp)

Dunno, it looks to me like every point on the extended solar panel has a view of Earth. Can't paint that black.

When Starship is launching them they could easily have the mass budget to have a black fold-out sail/umbrella/etc to shield it.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Herb Schaltegger on 10/17/2019 12:16 am

When Starship is launching them they could easily have the mass budget to have a black fold-out sail/umbrella/etc to shield it.

That would drastically increase the coefficient of drag, reduce operational lifetimes of each satellite and ultimately drive up operational costs of the constellation with reduced per-vehicle operational lifetimes.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Nomadd on 10/17/2019 12:34 am
 What does the non working side of the solar panels look like?
Title: Re: Starlink : General Discussion - Thread 2
Post by: ZChris13 on 10/17/2019 02:12 am
What does the non working side of the solar panels look like?
Does it matter? It's in shadow, by design. At most you're getting earthshine.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Nomadd on 10/17/2019 03:10 am
What does the non working side of the solar panels look like?
Does it matter? It's in shadow, by design. At most you're getting earthshine.
It's data. Ignoring possible factors because you don't think they'll matter is a well paved road. There are reasons they might not want the working side of the panel full on to the sun at all times.
 One way to keep the panel from collecting heat when you don't need to push electrons is keeping it edge on. The other way is to make the back side really reflective. Look at the ISS panels.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Norm38 on 10/17/2019 03:47 am
On painting satellites black:   The DOD already knows, but they're not going to tell you.
Title: Re: Starlink : General Discussion - Thread 2
Post by: OTV Booster on 10/17/2019 04:11 am
Two points.

First, is the render above showing a deployed panel or a deploying panel? I understand that they are getting higher off axis efficiencies these days but if extending the panel dead flat or close to it will fix the problem, then fix the problem.

Second, every photon that reflects off the panel is a wasted photon. Optical coatings are fully capable of damping reflections quite a bit.

Unfortunately coatings are expensive so COTS might not be the way to go. On the upside coatings mass nothing and by increasing efficiency they drop the panel size and mass. Drag goes down too so maybe less prop mass for station keeping. Maybe, just maybe, they can squeeze a couple more birds on an F9.

Phil
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 10/17/2019 05:39 am
I wouldn't assume that SpaceX actually intends to launch 30k more satellites.  They may just be filing extra orbits to give themselves more flexibility for future deployments.

Keyword is successive, not simultaneously.

What does successive mean in this context? ITU approval has a time limit (6 years?), if they don't use it within the time limit they'll lose it. So they can't file now for an orbit that they won't use for another 10 years for example.

If each satellite in the constellation needs replacing every 5 years, plus accounting for a non-zero failure rate, they may need 30,000 birds a lot sooner than first-blush impressions indicate

This.

Not this.  Those filings have nothing to do with the replacement cycle.
Title: Re: Starlink : General Discussion - Thread 2
Post by: woods170 on 10/17/2019 07:30 am
I wouldn't assume that SpaceX actually intends to launch 30k more satellites.  They may just be filing extra orbits to give themselves more flexibility for future deployments.

Keyword is successive, not simultaneously.

What does successive mean in this context? ITU approval has a time limit (6 years?), if they don't use it within the time limit they'll lose it. So they can't file now for an orbit that they won't use for another 10 years for example.

If each satellite in the constellation needs replacing every 5 years, plus accounting for a non-zero failure rate, they may need 30,000 birds a lot sooner than first-blush impressions indicate

This.

Not this.  Those filings have nothing to do with the replacement cycle.

That is your opinion, which I don't share. But before we go into a lengthy exchange I suggest we agree to disagree.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 10/17/2019 02:20 pm
I wouldn't assume that SpaceX actually intends to launch 30k more satellites.  They may just be filing extra orbits to give themselves more flexibility for future deployments.

Keyword is successive, not simultaneously.

What does successive mean in this context? ITU approval has a time limit (6 years?), if they don't use it within the time limit they'll lose it. So they can't file now for an orbit that they won't use for another 10 years for example.

If each satellite in the constellation needs replacing every 5 years, plus accounting for a non-zero failure rate, they may need 30,000 birds a lot sooner than first-blush impressions indicate

This.

Not this.  Those filings have nothing to do with the replacement cycle.

That is your opinion, which I don't share. But before we go into a lengthy exchange I suggest we agree to disagree.

Actually I'm not ok with that.  You don't need additional slots filed for replacements.  If you think these have anything to do with replacements you need to state why you think that is so.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 10/17/2019 03:20 pm
ITU filings are for payloads (not necessarily individual satellites) transmitting at particular frequencies in particular orbits.  SpaceX keeps changing their orbits, and has applied for payloads in different frequency ranges, so these 30,000 could include new parameters and frequencies for the previously filed 12,000 satellites.
Title: Re: Starlink : General Discussion - Thread 2
Post by: fl1034 on 10/18/2019 03:51 am
It's been quite a while since Falcon 9's last mission. When's the next batch of Starlink coming?
Title: Re: Starlink : General Discussion - Thread 2
Post by: docmordrid on 10/18/2019 04:49 am
SpaceFlightNow has 4 StarLink launches with "TBD" NETs between now and the end of December.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Comga on 10/20/2019 04:59 am
SpaceFlightNow has 4 StarLink launches with "TBD" NETs between now and the end of December.

During the same period some people are also expecting Santa Claus.

There was a statement that there could be two more Starlink launches after the October 17 and November 4 Starlink launches. We know those are not happening. The SFN info is likely just that the launches will probably happen but not start this month.
There are remarkably few launches with scheduled dates.
Title: Re: Starlink : General Discussion - Thread 2
Post by: FutureSpaceTourist on 10/22/2019 06:05 am
twitter.com/elonmusk/status/1186523464712146944

Quote
Sending this tweet through space via Starlink satellite 🛰

https://twitter.com/elonmusk/status/1186524008621043713

Quote
Whoa, it worked!!
Title: Re: Starlink : General Discussion - Thread 2
Post by: sferrin on 10/22/2019 10:50 am
I can't help but think that the government has CALEA problems with StarLink.
https://www.eff.org/issues/calea (https://www.eff.org/issues/calea)

Why would it be any different than any other satellite communications network?
Title: Re: Starlink : General Discussion - Thread 2
Post by: watermod on 10/23/2019 02:21 am
I can't help but think that the government has CALEA problems with StarLink.
https://www.eff.org/issues/calea (https://www.eff.org/issues/calea)

Why would it be any different than any other satellite communications network?

You have to know CALEA and really think about it.  (I had to deal with it at a now pretty much extinct cellular manufacturer when designing call flows etc..) 

I saw the initial StarLink as being designed NOT to BE an End to End user service that could be considered a telephone leg in the CALEA worldview but rather as a point in a service backbone leg.  This is evident when the endpoint is router with WiFi and not say a phone.    It becomes more obviously with the Sat to Sat laser connections as communications becomes so much more efficient when it doesn't need to go through central nodes on Earth.   

Currently CALEA requires ALL data calls and a random % (this keeps changing but usually 25 to 35 percent  voice calls) to be echoed by the central offices directly to the FBI.  The current StarLink does not appear to be designed with a central office model  The model is communicating nodes with soon fast laser routes to other nodes.  It is obvious that some huge backbone channeling all the StarLink traffic to the FBI would destroy the functional efficiency of StarLink (as it would require a central office POV overlay to ship to the FBI) and most of it's advantages. So it can not be construed as a telephony device or it gets crippled and the FBI gets overwhelmed with massive amounts of data. 

I could go into more detail but look at CALEA.

Title: Re: Starlink : General Discussion - Thread 2
Post by: sferrin on 10/23/2019 10:08 am
Currently CALEA requires ALL data calls and a random % (this keeps changing but usually 25 to 35 percent  voice calls) to be echoed by the central offices directly to the FBI.

That would suggest that ALL internet data in the US gets echoed by the FBI.  Is that the case?  If that's a requirement how is it that SpaceX didn't know about it?  If SpaceX did know why wouldn't they have addressed it?  Seems silly that they (and others) would just start building networks if they knew the FBI would stop them.  (I don't expect you to have the answers. Just thinking out loud as it were.)
Title: Re: Starlink : General Discussion - Thread 2
Post by: ChrisC on 10/23/2019 12:40 pm
Very interesting comment from watermod, but can this thread stay focused on this flight?  Surely there is another thread where Starlink topology has been / is being discussed, maybe even CALEA compliance.
Title: Re: Starlink : General Discussion - Thread 2
Post by: pippin on 10/23/2019 12:41 pm
Doesn’t CALEA only apply to calls (even if they are VoIP), not other data traffic?
Are WhatsApp, FB etc. calls currently compliant?
Title: Re: Starlink : General Discussion - Thread 2
Post by: yokem55 on 10/23/2019 01:22 pm
My personal experience (small clec/isp noc guy) with Calea is that it is only applicable to voice traffic interacting with the pstn, and then only with a valid warrant (company policy). That said if a warrant is dropped in our laps, there needs to be infrastructure in place, ready to go immediately, for the calls of the warrant target to be monitored by the applicable law enforcement agency.

So different companies can implement this immediate availability in different ways. Some might just keep packet captures of everything voice related for a short period of time, long enough for law enforcement to get the right stuff. Others (ours) is to build the infrastructure to generate those targeted, narrow, captures on demand.
Title: Re: Starlink : General Discussion - Thread 2
Post by: meberbs on 10/23/2019 04:43 pm
Currently CALEA requires ALL data calls and a random % (this keeps changing but usually 25 to 35 percent  voice calls) to be echoed by the central offices directly to the FBI.

That would suggest that ALL internet data in the US gets echoed by the FBI.  Is that the case?  If that's a requirement how is it that SpaceX didn't know about it?  If SpaceX did know why wouldn't they have addressed it?  Seems silly that they (and others) would just start building networks if they knew the FBI would stop them.  (I don't expect you to have the answers. Just thinking out loud as it were.)
As mentioned above, this is not mission specific, so it belongs in the general Starlink discussion thread but this is important to say:

What watermod described is completely unconstitutional. It is not even close to what is required by the law referenced https://en.wikipedia.org/wiki/Communications_Assistance_for_Law_Enforcement_Act which just requires wiretapping of specific people with a warrant to be possible.

@watermod: If you actually have experience with what you described please talk to appropriate authorities and provide any evidence you have of this gross wrongdoing. I recommend starting by talking to the Electronic Frontier Foundation  (EFF) which is a nonprofit which exists specifically to investigate and seek justice in exactly this kind of situation.

Also:
I saw the initial StarLink as being designed NOT to BE an End to End user service that could be considered a telephone leg in the CALEA worldview but rather as a point in a service backbone leg.
Starlink has been planned as an end user service from the very beginning, though long term backhaul may be a large fraction of their business. SpaceX will be an ISP and as far as I can tell ISPs have no obligations under CALEA.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Tulse on 10/23/2019 05:36 pm
Did I miss mention of this in some other place?: Musk's Satellite Project Testing Encrypted Internet With Military Planes (https://www.nytimes.com/reuters/2019/10/23/business/23reuters-spacex-starlink-airforce.html):

"The Air Force is using SpaceX's fledgling satellite network to test encrypted internet services for a number of military planes, the space company's president said on Tuesday, detailing results for the first customer of Elon Musk's planned constellation of thousands of broadband-beaming satellites."
[...]
"The Air Force program, known as Global Lightning, started testing with SpaceX in early 2018 and used Starlink's first two test satellites to beam to terminals fixed to a C-12 military transport plane in flight, demonstrating internet speeds of 610 megabits per-second, SpaceX Senior Vice President Tim Hughes said. That's fast enough to download a movie in under a minute."
[...]
"Shotwell said the program, part of a $28 million Pentagon contract awarded to SpaceX in late 2018, is ongoing and expects to test Starlink with "a number" of additional military aircraft types. That contract also includes testing communications between satellites in orbit."
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 10/23/2019 05:46 pm
Did I miss mention of this in some other place?: Musk's Satellite Project Testing Encrypted Internet With Military Planes (https://www.nytimes.com/reuters/2019/10/23/business/23reuters-spacex-starlink-airforce.html):

We knew they had military contracts to test Starlink, not sure how far back in the thread that would be.  Some of these details are new.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Rondaz on 10/23/2019 11:09 pm
SpaceX plans to launch more than 1,000 Starlink satellites by the end of 2020, and the service already seems to be partially working after a tweet by Musk via Starlink.

https://twitter.com/Astro_Jonny/status/1186973017227825152
Title: Re: Starlink : General Discussion - Thread 2
Post by: FutureSpaceTourist on 10/25/2019 04:17 pm
Quite a lot on Starlink in this:

https://twitter.com/bluemoondance74/status/1187752868939468801

Quote
[email protected] President/ COO Gwynne Shotwell speaking to Baron Funds CEO/ CIO Ron Baron at the annual Baron Investment Conference at the @MetOpera
Conf details: baronfunds.com/baron-conferen…
(Be sure to see full thread below)

Michael Sheetz’s twitter thread quotes (https://twitter.com/thesheetztweetz/status/1187741337455648768) some key points from Gwynne’s remarks.

She throws some shade at Blue Origin for not yet making orbit.

Couple of Starlink quotes:

https://twitter.com/thesheetztweetz/status/1187747359452729346

Quote
Shotwell: Starlink satellites will have roughly a 5 year life in orbit before we refresh.

Morgan Stanley estimated this week how much it would cost to deploy our satellites "and they were wayyyyyyyy off."

https://twitter.com/thesheetztweetz/status/1187748549313941507

Quote
Shotwell: SpaceX's Starlink is way less expensive than OneWeb and "17 times better or cheaper."

"Jeff Bezos wants to start a constellation and he's years behind."
Title: Re: Starlink : General Discussion - Thread 2
Post by: spacenut on 10/25/2019 07:23 pm
How many Starlink satellites are they manufacturing a month/week?  Is this what is holding up the launches?
Title: Re: Starlink : General Discussion - Thread 2
Post by: biosehnsucht on 10/25/2019 08:17 pm
Seems to me the obvious solution to CALEA is to not natively support voice calls or the termination thereof, and just let end users use whatever VoIP provider they want and thus make that the VoIP provider's problem on their end.

Being a pure IP data as data only carrier with no special handling to convert to/from PSTN/etc would mean CALEA doesn't apply directly but only to the service on other other end of a VoIP stream, so shouldn't impact Starlink efficiency.
Title: Re: Starlink : General Discussion - Thread 2
Post by: docmordrid on 10/26/2019 02:10 am
Michael Sheetz ✔ @thesheetztweetz
Replying to @thesheetztweetz
Shotwell: Next year we're going to be 60 Starlink satellites "every other week."

"Once we get to 1200 satellites we will have coverage of the whole globe."
|
Michael Sheetz ✔ @thesheetztweetz
Baron: How many satellites do we have right now?

Shotwell: About 1500.


https://twitter.com/thesheetztweetz/status/1187746742449721345
Title: Re: Starlink : General Discussion - Thread 2
Post by: aero on 10/26/2019 02:35 am
Clarify, is that 1500 satellites on orbit now?
Title: Re: Starlink : General Discussion - Thread 2
Post by: su27k on 10/26/2019 03:00 am
Clarify, is that 1500 satellites on orbit now?

She meant there're currently ~1500 active satellites in orbit, launched by everybody/humanity. @thesheetztweetz clarified this on reddit (https://www.reddit.com/r/spacex/comments/dmzp2q/thesheetztweetz_on_twitter_full_house_at_the/f578xzn/):

Quote
Not Starlink, satellites in general.
Title: Re: Starlink : General Discussion - Thread 2
Post by: su27k on 10/26/2019 03:06 am
SpaceX's proposed procedure for next launch, pending approval of their modification request.


Re: Space Exploration Holdings, LLC, IBFS File No. SAT-STA-20190924-00098;
SpaceX Services, Inc., IBFS File Nos. SES-STA-20190925-01225 through -01234
and -01242 through -01244

Dear Ms. Dortch:

Space Exploration Holdings, LLC and SpaceX Services, Inc. (collectively, “SpaceX”)
have filed the above referenced requests for special temporary authority (“STA”) for their
respective space and earth stations to communicate during the early portions of the mission after
the next launch of satellites for SpaceX’s non-geostationary orbit constellation. In order to aid the
Commission’s evaluation of those applications, this letter provides supplemental detail of the
phases planned for this launch and deployment of satellites.

Upon launch, SpaceX will insert the satellites in a circular orbit at an injection altitude of
approximately 280 km.


 During the first week following deployment, SpaceX will establish contact with all satellites
and begin to orbit raise them all toward an altitude of 350 km over the course of two weeks.

 Following initial testing, 20 of these satellites will be raised further to the operational altitude
of 550 km. These satellites will be deployed to an orbital plane already covered by SpaceX’s
current authorization.

 The remaining satellites will stay at the 350 km altitude for at least 40 days before orbit
raising to the operational altitude of 550 km. These satellites would be deployed in one of
the new orbital planes covered by SpaceX’s pending modification application.

SpaceX will, of course, coordinate the movement of its satellites with other affected parties,
including NASA with respect to the International Space Station.

Would they be able to squeeze in some more payload by launching to such a low orbit?
Title: Re: Starlink : General Discussion - Thread 2
Post by: docmordrid on 10/27/2019 01:04 am
So, the satellite-to-satellite laser interlinks go live next year.

Gwynne Shotwell,

CNN... (https://www.cnn.com/2019/10/26/tech/spacex-starlink-elon-musk-tweet-gwynne-shotwell/index.html)

Quote
>
The 60 satellites that we already flew are capable of operations, but the next version will have upgraded technology. By late next year, we'll be flying satellite with lasers that allow them to talk to each other in space and share data, which ensures customers will never lose service.
>
In countries where we can, we are likely to go directly to consumers. We'll have the full team of salespeople and tech support. Though, the better engineering that we do on the user terminal, the less service people we will need.
>
Title: Re: Starlink : General Discussion - Thread 2
Post by: Semmel on 10/27/2019 07:35 am
So, the satellite-to-satellite laser interlinks go live next year.

Gwynne Shotwell,

CNN... (https://www.cnn.com/2019/10/26/tech/spacex-starlink-elon-musk-tweet-gwynne-shotwell/index.html)

Quote
>
The 60 satellites that we already flew are capable of operations, but the next version will have upgraded technology. By late next year, we'll be flying satellite with lasers that allow them to talk to each other in space and share data, which ensures customers will never lose service.
>
In countries where we can, we are likely to go directly to consumers. We'll have the full team of salespeople and tech support. Though, the better engineering that we do on the user terminal, the less service people we will need.
>

Thank you, finally some information on this. "late next year" can start say, in September? But it practically means that the first batch of production satellites dont have the laser links and are bent pipe only. I wouldnt be surprised if the first 1200 sats that they say was the limit to offer the service to customers are all bent pipe.
Title: Re: Starlink : General Discussion - Thread 2
Post by: geza on 10/27/2019 09:01 am
So, the satellite-to-satellite laser interlinks go live next year.

Gwynne Shotwell,

CNN... (https://www.cnn.com/2019/10/26/tech/spacex-starlink-elon-musk-tweet-gwynne-shotwell/index.html)


Thank you, finally some information on this. "late next year" can start say, in September? But it practically means that the first batch of production satellites dont have the laser links and are bent pipe only. I wouldnt be surprised if the first 1200 sats that they say was the limit to offer the service to customers are all bent pipe.

It is probably a very difficult development. Good to have the confimation that it is still in the pipe. I am sure that Elon wants broadband connection for the very first Mars landing envisaged for '22 - which is already the next level of development.

Is there a serious discussion on the technicalities on the laser links somewhere?
Title: Re: Starlink : General Discussion - Thread 2
Post by: guckyfan on 10/27/2019 10:17 am
I am thinking now that the reason for laser link delay is the wish to deploy an operational constellation ASAP. Laser links will make the sats bigger and heavier, which means more launches to reach operational state. Get to the initial ~1500 without and then switch to sats using laser link.
Title: Re: Starlink : General Discussion - Thread 2
Post by: dondar on 10/27/2019 06:25 pm
I am thinking now that the reason for laser link delay is the wish to deploy an operational constellation ASAP. Laser links will make the sats bigger and heavier, which means more launches to reach operational state. Get to the initial ~1500 without and then switch to sats using laser link.
the reason of the delay is Elon's decision to redesign laser mirrors (there was considerable noise from "concerned citizens" over  risk from falling star-links. Mirrors were ones of the very few satellite parts which can survive the landing burn). The only way for them to do that in relatively short time and in controllable manner was to bring laser link construction in house. They have started to do that just 3 months ago.
Title: Re: Starlink : General Discussion - Thread 2
Post by: guckyfan on 10/27/2019 06:30 pm
I am thinking now that the reason for laser link delay is the wish to deploy an operational constellation ASAP. Laser links will make the sats bigger and heavier, which means more launches to reach operational state. Get to the initial ~1500 without and then switch to sats using laser link.
the reason of the delay is Elon's decision to redesign laser mirrors (there was considerable noise from "concerned citizens" over  risk from falling star-links. Mirrors were ones of the very few satellite parts which can survive the landing burn). The only way for them to do that in relatively short time and in controllable manner was to bring laser link construction in house. They have started to do that just 3 months ago.

True for a constellation of many thousand sats. The initial few hundreds until they have a different mirror would not cause realistic concern. Lots of sats and rocket stages have components that reach the ground.

If that were the reason they could launch hundreds of sats and then change the mirror material.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Mondagun on 10/27/2019 06:42 pm
the reason of the delay is Elon's decision to redesign laser mirrors (there was considerable noise from "concerned citizens" over  risk from falling star-links. Mirrors were ones of the very few satellite parts which can survive the landing burn). The only way for them to do that in relatively short time and in controllable manner was to bring laser link construction in house. They have started to do that just 3 months ago.
Source?
Title: Re: Starlink : General Discussion - Thread 2
Post by: OTV Booster on 10/27/2019 06:59 pm
I am thinking now that the reason for laser link delay is the wish to deploy an operational constellation ASAP. Laser links will make the sats bigger and heavier, which means more launches to reach operational state. Get to the initial ~1500 without and then switch to sats using laser link.
the reason of the delay is Elon's decision to redesign laser mirrors (there was considerable noise from "concerned citizens" over  risk from falling star-links. Mirrors were ones of the very few satellite parts which can survive the landing burn). The only way for them to do that in relatively short time and in controllable manner was to bring laser link construction in house. They have started to do that just 3 months ago.

True for a constellation of many thousand sats. The initial few hundreds until they have a different mirror would not cause realistic concern. Lots of sats and rocket stages have components that reach the ground.

If that were the reason they could launch hundreds of sats and then change the mirror material.

PR, especially in an environment with an ever increasing population of luddites, is important. With 30,000 sat and a five year lifetime, once the pipeline of decaying sats is filled this averages out to 16+ sats a day thundering down out of the sky. Pardon the hyperbole.

If each has one or two bits that make it down you become an open target. It doesn’t matter what else is raining down. If somebody gets clocked the problems go exponential. Low probability, high consequences.

Even with only a small initial deployment of reentry survivors someone will make the extrapolation and explaining the real plan will be seen by some as damage control.

Musk wants to stand on both the moral and PR high ground. Isn’t that a bit refreshing?

Phil
Title: Re: Starlink : General Discussion - Thread 2
Post by: TheRadicalModerate on 10/27/2019 07:36 pm
Thank you, finally some information on this. "late next year" can start say, in September? But it practically means that the first batch of production satellites dont have the laser links and are bent pipe only. I wouldnt be surprised if the first 1200 sats that they say was the limit to offer the service to customers are all bent pipe.

I keep wondering if they're going to deploy ground-bounce relay stations, or even if they're going to have user terminals do double duty as relays.

Obviously you can reach a whole bunch of people in remote areas and bent-pipe their traffic to somewhere within the spot that has terrestrial internet edge access.  But that's not going to be true everywhere, and it's especially not true for intercontinental aircraft and maritime applications.

It's probably easy to plunk some relays down on land to support super-remote fixed-location customers, but I'd think that they'd want to get the aircraft and maritime applications up ASAP.  With those, another aircraft or ship acting as a relay would be a lot more cost-effective than a set of buoys out at sea--and much faster to deploy.  It's obviously not the highest bandwidth solution you can think of, but if the deployment proceeds on schedule, you'll only have grumbling about performance for a few months.
Title: Re: Starlink : General Discussion - Thread 2
Post by: joek on 10/27/2019 08:13 pm
...
It's probably easy to plunk some relays down on land to support super-remote fixed-location customers, but I'd think that they'd want to get the aircraft and maritime applications up ASAP.  With those, another aircraft or ship acting as a relay would be a lot more cost-effective than a set of buoys out at sea--and much faster to deploy.  It's obviously not the highest bandwidth solution you can think of, but if the deployment proceeds on schedule, you'll only have grumbling about performance for a few months.

I hope and expect that in the long term Starlink does not make such differentiation.  Satellites, ground stations, whatever ... they're all essentially part of a giant mesh network.  Once they have the hardware in place (ground-sat, sat-ground, sat-sat, ...), communications the rest is a software-routing problem, which they will presumably improve over time--assuming the ground components are trusted or semi-trusted members of the mesh.  Moreover, no reason why the individual in-space or ground components need to do all the work as autonomous elements.  Expect "Starlink central" to provide periodic adult supervision and assist.
Title: Re: Starlink : General Discussion - Thread 2
Post by: TheRadicalModerate on 10/27/2019 08:19 pm
I can't help but think that the government has CALEA problems with StarLink.
https://www.eff.org/issues/calea (https://www.eff.org/issues/calea)

Why would it be any different than any other satellite communications network?

You have to know CALEA and really think about it.  (I had to deal with it at a now pretty much extinct cellular manufacturer when designing call flows etc..) 

I saw the initial StarLink as being designed NOT to BE an End to End user service that could be considered a telephone leg in the CALEA worldview but rather as a point in a service backbone leg.  This is evident when the endpoint is router with WiFi and not say a phone.    It becomes more obviously with the Sat to Sat laser connections as communications becomes so much more efficient when it doesn't need to go through central nodes on Earth.   

Currently CALEA requires ALL data calls and a random % (this keeps changing but usually 25 to 35 percent  voice calls) to be echoed by the central offices directly to the FBI.  The current StarLink does not appear to be designed with a central office model  The model is communicating nodes with soon fast laser routes to other nodes.  It is obvious that some huge backbone channeling all the StarLink traffic to the FBI would destroy the functional efficiency of StarLink (as it would require a central office POV overlay to ship to the FBI) and most of it's advantages. So it can not be construed as a telephony device or it gets crippled and the FBI gets overwhelmed with massive amounts of data. 

I could go into more detail but look at CALEA.

CALEA has applied to ISPs and VoIP service providers for over 15 years now.  I've forgotten the architectural details, but the intercept points don't have to be in central offices any more.  They do still have to format the data and throw it over the wall to the the intercepting authority, to prevent law enforcement from monkeying directly with the bearer channels and obtaining unwarranted data (although the stuff that Snowden leaked seems to indicate that numerous federal agencies have made a mockery of that restriction).

AFAIK, SpaceX isn't planning on marketing its own VoIP or text service; other service providers will use Starlink over the top, just like any other routing fabric.  Most, but not all, VoIP providers have some sort of call agent in the signaling path, and can divert the flow to a bridge or packet-cloner to do the lawful intercept.

In general, it's very hard to intercept an internet communications service that uses some squirrelly protocol and doesn't have a centralized signaling service.  But there's no functional difference in that case between a terrestrial router and one that happens to be lounging about in LEO.  Starlink's just another set of routers.
Title: Re: Starlink : General Discussion - Thread 2
Post by: TheRadicalModerate on 10/27/2019 08:27 pm
I hope and expect that in the long term Starlink does not make such differentiation.  Satellites, ground stations, whatever ... they're all essentially part of a giant mesh network.  Once they have the hardware in place (ground-sat, sat-ground, sat-sat, ...), communications the rest is a software-routing problem, which they will presumably improve over time--assuming the ground components are trusted or semi-trusted members of the mesh.  Moreover, no reason why the individual in-space or ground components need to do all the work as autonomous elements.  Expect "Starlink central" to provide periodic adult supervision and assist.

There are some fairly serious issues with recruiting user terminals to act as routers.  There are obvious performance, privacy, and security problems.  They're fixable, but they incur a lot of engineering and regulatory cost.

In general, you engineer your network(s) to have an edge for customer access and a backbone for transit.  It's pretty easy to build a satellite that can do both functions in a single package, but it's a lot harder to put backbone functionality into a piece of customer premises equipment.  Customers have an unfortunate habit of trying to monkey with their CPEs, and sometimes they're successful.  The temptation to do so is amplified if they think they can break into the backbone by doing so.

PS:  That said, it'll be very tempting for SpaceX to use the CPE as a temporary solution until the sat-to-sat lasers are up and running.  If they don't, they're on the hook for a lot of secure ground-bounce equipment that will have a very short life.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 10/27/2019 09:30 pm
the reason of the delay is Elon's decision to redesign laser mirrors (there was considerable noise from "concerned citizens" over  risk from falling star-links. Mirrors were ones of the very few satellite parts which can survive the landing burn). The only way for them to do that in relatively short time and in controllable manner was to bring laser link construction in house. They have started to do that just 3 months ago.

I don't think that is true.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Rondaz on 10/27/2019 10:03 pm
[email protected]'s Shotwell boldly claims #Starlink would have 17 times higher spectral efficiency over @OneWeb:
"Our competitors are largely these new entrants to the market. OneWeb? We are 17 times better per bit,"

https://twitter.com/Megaconstellati/status/1188551135558324231
Title: Re: Starlink : General Discussion - Thread 2
Post by: freddo411 on 10/28/2019 12:56 am
I hope and expect that in the long term Starlink does not make such differentiation.  Satellites, ground stations, whatever ... they're all essentially part of a giant mesh network.  Once they have the hardware in place (ground-sat, sat-ground, sat-sat, ...), communications the rest is a software-routing problem, which they will presumably improve over time--assuming the ground components are trusted or semi-trusted members of the mesh.  Moreover, no reason why the individual in-space or ground components need to do all the work as autonomous elements.  Expect "Starlink central" to provide periodic adult supervision and assist.

There are some fairly serious issues with recruiting user terminals to act as routers.  There are obvious performance, privacy, and security problems.  They're fixable, but they incur a lot of engineering and regulatory cost.

In general, you engineer your network(s) to have an edge for customer access and a backbone for transit.  It's pretty easy to build a satellite that can do both functions in a single package, but it's a lot harder to put backbone functionality into a piece of customer premises equipment.  Customers have an unfortunate habit of trying to monkey with their CPEs, and sometimes they're successful.  The temptation to do so is amplified if they think they can break into the backbone by doing so.

PS:  That said, it'll be very tempting for SpaceX to use the CPE as a temporary solution until the sat-to-sat lasers are up and running.  If they don't, they're on the hook for a lot of secure ground-bounce equipment that will have a very short life.

Let's talk USA for a moment.   How many ground terminals do you think are needed such that any sat talking to a customer in the USA can see at least one of the ground routing stations?   Based upon the satellite footprints I've seen it looks to be about 5 or so.     It's seems like they would need that equipment even after they become capable of inter satellite linkages as they have to "land" the packets eventually in any case.   

The routes aren't any shorter/faster than traditional internet via fiber, (maybe a bit worse) but I don't see them having to setup many more ground based routers / internet gateways now than for later network architectures. 
Title: Re: Starlink : General Discussion - Thread 2
Post by: docmordrid on 10/28/2019 03:13 am
A hard number for StarLinks/Starship.

Shotwell at the Baron Fund investor conference in NYC.

CNBC... (https://www.cnbc.com/2019/10/27/spacex-president-we-will-land-starship-on-moon-before-2022.html)

Quote
>
Once SpaceX is flying Starship regularly, she said the rocket will be able to launch nearly seven times as many Starlink satellites at once.

"Starship can take 400 satellites at a time," Shotwell said.
>
Title: Re: Starlink : General Discussion - Thread 2
Post by: TheRadicalModerate on 10/28/2019 04:03 am
I hope and expect that in the long term Starlink does not make such differentiation.  Satellites, ground stations, whatever ... they're all essentially part of a giant mesh network.  Once they have the hardware in place (ground-sat, sat-ground, sat-sat, ...), communications the rest is a software-routing problem, which they will presumably improve over time--assuming the ground components are trusted or semi-trusted members of the mesh.  Moreover, no reason why the individual in-space or ground components need to do all the work as autonomous elements.  Expect "Starlink central" to provide periodic adult supervision and assist.

There are some fairly serious issues with recruiting user terminals to act as routers.  There are obvious performance, privacy, and security problems.  They're fixable, but they incur a lot of engineering and regulatory cost.

In general, you engineer your network(s) to have an edge for customer access and a backbone for transit.  It's pretty easy to build a satellite that can do both functions in a single package, but it's a lot harder to put backbone functionality into a piece of customer premises equipment.  Customers have an unfortunate habit of trying to monkey with their CPEs, and sometimes they're successful.  The temptation to do so is amplified if they think they can break into the backbone by doing so.

PS:  That said, it'll be very tempting for SpaceX to use the CPE as a temporary solution until the sat-to-sat lasers are up and running.  If they don't, they're on the hook for a lot of secure ground-bounce equipment that will have a very short life.

Let's talk USA for a moment.   How many ground terminals do you think are needed such that any sat talking to a customer in the USA can see at least one of the ground routing stations?   Based upon the satellite footprints I've seen it looks to be about 5 or so.     It's seems like they would need that equipment even after they become capable of inter satellite linkages as they have to "land" the packets eventually in any case.   

The routes aren't any shorter/faster than traditional internet via fiber, (maybe a bit worse) but I don't see them having to setup many more ground based routers / internet gateways now than for later network architectures.

Footprints for 550 km birds are--what?--630 km?  That makes it more like 10-15 for the initial coverage area, but it's not a huge number.  And I think you're right that it's likely that there are high-bandwidth ground stations located near more than 15 IXPs, even to start with.

However, I'd think that they need the air and maritime stuff up pretty quickly, and then they're going to need to ground-bounce (or air- or sea-bounce) a lot more stuff, in areas where deploying dedicated stations will be expensive, especially since they're only going to be needed for a very short period of time.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Nomadd on 10/28/2019 04:20 am
 It might have been covered, but I assumed the minimum elevation mentioned was for users. Starlink routing stations won't be using $100 user antennas, and will be located for good sky views. I'd be surprised if they couldn't go down to 5 degrees with them.
 1.2m ku band dishes are cleared for that.
Title: Re: Starlink : General Discussion - Thread 2
Post by: freddo411 on 10/28/2019 04:26 am


Footprints for 550 km birds are--what?--630 km?  That makes it more like 10-15 for the initial coverage area, but it's not a huge number.  And I think you're right that it's likely that there are high-bandwidth ground stations located near more than 15 IXPs, even to start with.

However, I'd think that they need the air and maritime stuff up pretty quickly, and then they're going to need to ground-bounce (or air- or sea-bounce) a lot more stuff, in areas where deploying dedicated stations will be expensive, especially since they're only going to be needed for a very short period of time.

Yes.   Good point.   To provide services to ocean crossing ships and planes is going to realistically require (I suspect) intra-satellite links.   

I suppose domestic airlines would workout pretty well, as an initial customer.
Title: Re: Starlink : General Discussion - Thread 2
Post by: TripleSeven on 10/28/2019 04:33 am
It might have been covered, but I assumed the minimum elevation mentioned was for users. Starlink routing stations won't be using $100 user antennas, and will be located for good sky views. I'd be surprised if they couldn't go down to 5 degrees with them.
 1.2m ku band dishes are cleared for that.

they will finish the installation of the test system here...on WED but we cut down trees to give the system 10 degree access at the com site ....its odd to see it among the 300 foot ATT old long lines tower... :)
Title: Re: Starlink : General Discussion - Thread 2
Post by: Cheapchips on 10/28/2019 10:16 am
A hard number for StarLinks/Starship.

Shotwell at the Baron Fund investor conference in NYC.

CNBC... (https://www.cnbc.com/2019/10/27/spacex-president-we-will-land-starship-on-moon-before-2022.html)

Quote
>
Once SpaceX is flying Starship regularly, she said the rocket will be able to launch nearly seven times as many Starlink satellites at once.

"Starship can take 400 satellites at a time," Shotwell said.
>

If they achieve the <$10m launch cost they're expecting for SS then that's under a billion to launch the entire constellation.   Morgan Stanley's estimate is $60bn.  “They were way off,” Shotwell said.  ;D

It'd be nice to know how low they can go on satellite manufacturing costs.

Also, 400 sats per launch puts their replacement flights at around 20 a year, based on 5 yr satellite lifespan. 


 
Title: Re: Starlink : General Discussion - Thread 2
Post by: dondar on 10/28/2019 12:21 pm
the reason of the delay is Elon's decision to redesign laser mirrors (there was considerable noise from "concerned citizens" over  risk from falling star-links. Mirrors were ones of the very few satellite parts which can survive the landing burn). The only way for them to do that in relatively short time and in controllable manner was to bring laser link construction in house. They have started to do that just 3 months ago.
Source?
https://spectrum.ieee.org/tech-talk/aerospace/satellites/spacex-claims-to-have-redesigned-its-starlink-satellites-to-eliminate-casualty-risks

Quote
...As originally designed, nine pieces of each Starlink satellite, including thruster parts, reaction wheels used for maneuvering, and silicon carbide communications components (probably mirrors for intersatellite laser links), would have reached the surface, SpaceX acknowledged. Some of these would have had enough energy to injure or kill, although the company contended that even the flimsiest of shelters would have offered some protection.....
Title: Re: Starlink : General Discussion - Thread 2
Post by: dondar on 10/28/2019 12:34 pm
the reason of the delay is Elon's decision to redesign laser mirrors (there was considerable noise from "concerned citizens" over  risk from falling star-links. Mirrors were ones of the very few satellite parts which can survive the landing burn). The only way for them to do that in relatively short time and in controllable manner was to bring laser link construction in house. They have started to do that just 3 months ago.

I don't think that is true.
What part?
Elon decision? Being cornered by FCC and his legal advisers (costs of the insurance better said) he had asked if it's possible to eliminate hard to burn parts. Since the answer was yes, the command was "do it now". It is SpaceX after all, not Boeing.

"Concerned citizens" were true as well. beside very "concerned" letters from Oneweb and their buddies there was also "public" outcry not fundamentally different from the "OMG death to the free sky" outcry some months later. Considering very precisely directed outrage no less ridiculous as well.
3 months ago? The very relevant open job positions were closed in august.
They have intended to use out-of shelf solution. Absence of any relevant work force was direct give away.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Rondaz on 10/28/2019 12:57 pm
“the satellites can end up through the ground talking to each other” implies no crosslinks in the first 400 or even 1200 satellites (unsurprisingly since a major physical redesign would be needed)

https://twitter.com/TMFAssociates/status/1188630459770523648
Title: Re: Starlink : General Discussion - Thread 2
Post by: flyright on 10/28/2019 01:04 pm
It might have been covered, but I assumed the minimum elevation mentioned was for users. Starlink routing stations won't be using $100 user antennas, and will be located for good sky views. I'd be surprised if they couldn't go down to 5 degrees with them.
 1.2m ku band dishes are cleared for that.

they will finish the installation of the test system here...on WED but we cut down trees to give the system 10 degree access at the com site ....its odd to see it among the 300 foot ATT old long lines tower... :)

Perhaps I missed this in a previous post, but where is "here" (the location of the test system)?
Title: Re: Starlink : General Discussion - Thread 2
Post by: meberbs on 10/28/2019 01:10 pm
What part?
There is the part where you present speculation as if you had insider information and talked to Elon Musk himself about this. Claims that it specifically was "because lawyers" or "the FCC insisted" are simply not supported by public evidence. You are stating opinion and guesses as fact, which is not appropriate. For your first post it seemed like you were maybe an insider sharing new information, or quoting an insider. Your new post makes it clear this is not the case.

Looking at when job postings were closed does not support any of your conclusions. Companies can leave job postings up for months after they actually got filled. Just putting them up to begin with doesn't mean they don't already have anyone doing the described work with the relevant skills. Maybe they have been doing it for a year, but want more manpower. Maybe they have some staff that is moving on or retiring.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 10/28/2019 01:56 pm
It might have been covered, but I assumed the minimum elevation mentioned was for users. Starlink routing stations won't be using $100 user antennas, and will be located for good sky views. I'd be surprised if they couldn't go down to 5 degrees with them.
 1.2m ku band dishes are cleared for that.

In the US at least those elevations were for all ground stations.
Title: Re: Starlink : General Discussion - Thread 2
Post by: dondar on 10/28/2019 05:26 pm
What part?
There is the part where you present speculation as if you had insider information and talked to Elon Musk himself about this. Claims that it specifically was "because lawyers" or "the FCC insisted" are simply not supported by public evidence. You are stating opinion and guesses as fact, which is not appropriate. For your first post it seemed like you were maybe an insider sharing new information, or quoting an insider. Your new post makes it clear this is not the case.
FCC insisted twice on the recalculation of the risks and to study ways of their reduction.
The article I've linked was describing exactly last such instance.
 Starlink application was delayed (at least ones) as a result of not accepting specifically risk calculations.

The risks are coupled with the insurance costs (per satellite btw).

Quote
Looking at when job postings were closed does not support any of your conclusions. Companies can leave job postings up for months after they actually got filled. Just putting them up to begin with doesn't mean they don't already have anyone doing the described work with the relevant skills. Maybe they have been doing it for a year, but want more manpower. Maybe they have some staff that is moving on or retiring.
the laser link positions had appeared in June (some in April) and were filled up in august. there were no such job posting during all last 4 years. It's possible to track even people names. (no, I won't do it here).

 P.S. SpaceX is actually quite accurate with job postings. they get too many applicants for every of them.
I won't go into "insider thing". It's beyond silly. Everything I post is speculations.
Title: Re: Starlink : General Discussion - Thread 2
Post by: envy887 on 10/28/2019 07:54 pm
I won't go into "insider thing". It's beyond silly. Everything I post is speculations.

It's not silly, there are people here with contacts inside SpaceX who post information that is not speculation.

If you are speculating, or making deductions based on public info, you should make that clear. And posting your line of reasoning helps too.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Rondaz on 10/29/2019 06:45 pm
SpaceX takes 'prerequisite' step for Starlink Aussie approval

New satellite broadband service asks for regulatory permission.

By Ry Crozier Oct 29 2019 5:55AM

https://www.itnews.com.au/news/spacex-takes-prerequisite-step-for-starlink-aussie-approval-533089
Title: Re: Starlink : General Discussion - Thread 2
Post by: TheRadicalModerate on 10/29/2019 07:22 pm
Where is SpaceX wrt the ITU stuff needed to operate over international territory?  There are an awful lot of aircraft and maritime applications that happen over water.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Rondaz on 10/29/2019 10:47 pm
Meanwhile @OneWeb through its subsidiary "Network Access Associates Ltd (incorporated in the United Kingdom)" has been included in Australia's "Foreign Space Objects Determination" two years ago for which a separate consultation was held in August 2017:

https://twitter.com/Megaconstellati/status/1189277907362996226
Title: Re: Starlink : General Discussion - Thread 2
Post by: Rondaz on 10/31/2019 03:52 pm
Starlink orbit status. Around Oct 27, object 44240 (Starlink 26, in cyan) was lowered slightly out of the active constellation. Still no satellites deorbited: all 60 still being tracked. (Blue: Main constell; Red: satellites not in main constell;  Green: debris)

https://twitter.com/planet4589/status/1189928526478282752
Title: Re: Starlink : General Discussion - Thread 2
Post by: Rondaz on 11/03/2019 06:11 pm
Starlink is a very big deal!

CASEY HANDMER'S BLOG  NOVEMBER 2, 2019 CJHANDMER

https://caseyhandmer.wordpress.com/2019/11/02/starlink-is-a-very-big-deal/
Title: Re: Starlink : General Discussion - Thread 2
Post by: dondar on 11/03/2019 08:30 pm
I won't go into "insider thing". It's beyond silly. Everything I post is speculations.

It's not silly, there are people here with contacts inside SpaceX who post information that is not speculation.

If you are speculating, or making deductions based on public info, you should make that clear. And posting your line of reasoning helps too.
It would be very nice to see some (any) posts with insider information about Starlink....
Just as well it would be nice to make some reflections about what, how and when comes  out.

I've described my reasoning sufficiently. SpaceX vs FCC saga is free to access on FCC site. You need to parse OneWeb vs FCC though as well to understand. Probably Boeing and a few other relatives as well.
 Satellite insurance info is not free but is available, Starlink media saga of the last year is also freely available. Heck, even SpaceX job position history description is available on  the web and there is at least one source  with quite reasonable discussion about Starlink jobs evolution. (though jobs positions are incomplete, which is a pity because it led inevitably to incomplete conclusions).
Title: Re: Starlink : General Discussion - Thread 2
Post by: meberbs on 11/03/2019 09:18 pm
I won't go into "insider thing". It's beyond silly. Everything I post is speculations.

It's not silly, there are people here with contacts inside SpaceX who post information that is not speculation.

If you are speculating, or making deductions based on public info, you should make that clear. And posting your line of reasoning helps too.
It would be very nice to see some (any) posts with insider information about Starlink....
Just as well it would be nice to make some reflections about what, how and when comes  out.
L2 is the most likely place to find any insider updates on Starlink.

I've described my reasoning sufficiently. SpaceX vs FCC saga is free to access on FCC site. You need to parse OneWeb vs FCC though as well to understand. Probably Boeing and a few other relatives as well.
Your descriptions have been inconsistent with the actual facts available. For example, it is not strange for the FCC to ask for more detail on how a calculation is done. That in no way indicates that this ask is in anyway related to SpaceX's decision to remove the non-demisable mirrors. In fact the filings generally indicate that SpaceX is aiming for well over and beyond many regulations, because what the regulations allow is often not nearly good enough in this context from SpaceX's perspective.

Satellite insurance info is not free but is available, Starlink media saga of the last year is also freely available. Heck, even SpaceX job position history description is available on  the web and there is at least one source  with quite reasonable discussion about Starlink jobs evolution. (though jobs positions are incomplete, which is a pity because it led inevitably to incomplete conclusions).
It seems you are recognizing some of the problems with the data sources you were using to make assertions. Thank you.
Title: Re: Starlink : General Discussion - Thread 2
Post by: TorenAltair on 11/08/2019 01:25 am
New FCC decision
https://fcc.report/IBFS/SAT-STA-20190924-00098

Quote
Special temporary authority (STA) for a period of 60 days to conduct Launch and Early Orbit-Phase (LEOP) operations to perform TT&C necessary for orbit-raising of each of the 60 satellites to be imminently launched from the insertion altitude of 280 km to an altitude of 350 km for initial payload testing and then to raise 20 of those satellites to an previously authorized orbital plane at an altitude of 550 km and to test the communications payload on each of the 60 satellites. SpaceX’s request for authority to conduct LEOP operations and payload testing in planes proposed in the pending modification is deferred
Title: Re: Starlink : General Discussion - Thread 2
Post by: Rondaz on 11/08/2019 03:10 am
SpaceX’s Starlink satellite internet was tested by the US Air Force and the results are in..

By Jamie Groh Posted on November 7, 2019

https://www.teslarati.com/spacex-starlink-satellite-internet-us-air-force-testing/
Title: Re: Starlink : General Discussion - Thread 2
Post by: Star One on 11/08/2019 01:49 pm
https://youtu.be/KENaDXdm1sg
Title: Re: Starlink : General Discussion - Thread 2
Post by: Mandella on 11/09/2019 02:18 am
So it occurs to me to wonder, will this be the first product that Musk actively advertises to the general public? For all his reputation for PR stunts, neither Falcon 9s nor Teslas are advertised in the "buying ad time in various media" manner.

I'm thinking they are not going to be able to depend on word of mouth for Starlink, and are going to have to resort to traditional advertising -- commercials, banners, direct mailings, the whole shebang.

Going to be interesting to see what they come up with.
Title: Re: Starlink : General Discussion - Thread 2
Post by: ncb1397 on 11/09/2019 03:17 am
So it occurs to me to wonder, will this be the first product that Musk actively advertises to the general public? For all his reputation for PR stunts, neither Falcon 9s nor Teslas are advertised in the "buying ad time in various media" manner.

I'm thinking they are not going to be able to depend on word of mouth for Starlink, and are going to have to resort to traditional advertising -- commercials, banners, direct mailings, the whole shebang.

Going to be interesting to see what they come up with.

Does door to door at SolarCity count?
Title: Re: Starlink : General Discussion - Thread 2
Post by: TripleSeven on 11/09/2019 07:10 am
It's interesting that they are estimating based on existing Internet customers and not mentioning service to new markets such as the currently underserved and not served peoples of the world.

Cheap used cell phones are available to most of the 3rd world and developing. 3G data plans in India costs 1/10 of what we pay in the USA. So internet is available to most of the people of the world. The 3 billion people that don't have internet, it is mostly because they live on $5 per day and there is no price where it is affordable. SpaceX won't be fixing that.

Here are the potential markets where Starlink will have a huge advantage quickly and these markets are likely where it will strike first.

Cruise ships. There are 300+ cruise ships of significant size and there were 28 million plus passengers in 2018. They get pathetic slow satellite internet service plans right now and I recall paying $14 per day for that slow service. Cruise companies are definitely going to switch to buying internet service from Starlink in bulk as soon as it is available.

Airlines. The company Gogo had $900 million (Mostly USA only) in revenue in 2018 providing 3G internet service (very slow) to airlines. Gogo is a publicly traded stock (GOGO). I am considering shorting it. The market opportunity here for Starlink is way bigger than just the $900 million that Gogo makes in the USA/Canada market. Europe and Asia are also another few billion dollars $$$ in opportunity for Starlink.

Also basically every boat of any size is a potential customer of Starlink.

Container ships = 50,000
Mega Yachts = 10,000+
Regular Yachts = 250,000+ (wealthy doctors, investment bankers, small business owners, etc)
Commercial fishing ships = hundreds of thousands of large commercial fishing boats out there

300+ cruise ships carried over 28 million people in 2018.

There is several billion dollars in market opportunity right with that list. Starlink broadband will likely dominate these markets within a few years of being available. The current internet data speeds provided by satellites are just way too slow to compete.

Just my opinion.

and I think a really good opinion...I would offer this in comment and addition

one big customer you left out is the US military (and maybe militaries all over the world) .  The US military of all branches, including the USCG (not technically a military service now) is running test on the system as it is right now.  and from what I hear the results have really been quite positive.  The military was one of the things that helped Iridium at least survive and now prosper and they see Starlink as a nice transition from that for faster speeds...

I think the airline market is potentially big.  Airlines on long haul use the internet as a form of entertainment for people stuck in tubes for about half a day...anything that increased use, particularly when they can levy a sircharge in economy would be something that they would be interested in.

but for that very same reason I am curious as to how cruise ships will react to this.  everything you say about the cost of using the net on a ship is true...but really what they want you to do is to spend the time and money in their entertainment venues.  and I cannot imagine that anyone who is on a cruise ship, would spend a lot of time surfing the net for entertainment.  but I agree it probably will replace what is there now...and the cruise lines would make a sir charge on it

I will be very curious to see how it goes replacing land line subscribers.  I at first was skeptical...now am a little less skeptical...but it all depends on the price at least for me (and the antenna requirements for others) and the ultimate performance.  What Ihave seen of the military experiments has been well impressive.   but the antenna installation right now is non trivial...and you dont know how foreign governments are going to react to this.

another issue in the states is going to be how cable "services" are bundled...

but again so far what I have seen first hand...is impressive
Title: Re: Starlink : General Discussion - Thread 2
Post by: philw1776 on 11/09/2019 12:30 pm
Spend time on cruise social media.  #1 complaint on high end cruises (internet included in fare) is too slow internet.  Folks just love posting their photos and feel out of touch without their net fix.  Me, I enjoy the cruise and just read my email but the market is there.
Title: Re: Starlink : General Discussion - Thread 2
Post by: BZHSpace on 11/09/2019 12:34 pm
I think about Starlink's future and I believe that Starlink could be use as a constellation for Mars internet. When we talk about multiplanetary humanity, we have to think that human need various device on the place they live. Those needs could be internet and high speed communication on Mars.

What you think about that ?
Title: Re: Starlink : General Discussion - Thread 2
Post by: butters on 11/09/2019 01:24 pm
So it occurs to me to wonder, will this be the first product that Musk actively advertises to the general public? For all his reputation for PR stunts, neither Falcon 9s nor Teslas are advertised in the "buying ad time in various media" manner.

I'm thinking they are not going to be able to depend on word of mouth for Starlink, and are going to have to resort to traditional advertising -- commercials, banners, direct mailings, the whole shebang.

Going to be interesting to see what they come up with.

I don't see any reason for Starlink to diverge from the typical Elon strategy of accepting refundable deposits to reserve spots on the waiting list. The system is going to be supply-limited in the near term, if not by the capacity of the constellation than by the production rate for the user terminals. There will be excess demand, and customers will wait in line to get their terminal.
Title: Re: Starlink : General Discussion - Thread 2
Post by: JBF on 11/09/2019 01:26 pm
As a design concept with similar parts sure, but not as is.  Starlink requires a dedicated manufacturing facility and launch resources just to keep up with the replacement rate.  The first world wide Mars system will need to be geostationary.
Title: Re: Starlink : General Discussion - Thread 2
Post by: ZChris13 on 11/09/2019 01:28 pm
I think about Starlink's future and I believe that Starlink could be use as a constellation for Mars internet. When we talk about multiplanetary humanity, we have to think that human need various device on the place they live. Those needs could be internet and high speed communication on Mars.

What you think about that ?
As Starlink exists now?
No
As Starlink is publicly planned to exist in the future?
Almost
As Starlink could be potentially modified to exist?
Certainly.

My thoughts:
Delivery is nontrivial, but sounds doable. I'm sure there's a thread on this full of all sorts of amazing schemes.
Power supply is decreased per mass because of reduced insolation, which has cascading effects that make it just a little bit less amazing. But with Gwynne's recent statement on a notional four hundred Starlink satellites per Starship launch, I'm sure they can absorb some serious weight gain before they run into difficulties deploying them all.
One thing that will absolutely be needed is the laser links: their purpose is a global internet backbone, and with limited useful ground infrastructure that's the most important element for Mars.
The last big point of interest is the link back to Terra. This could fill a whole thread on its own, and my personal pet thought is big laser link telescopes. The exact details escape me but I have many questions. Point me towards a better thread and I would love to hash it out.

As a design concept with similar parts sure, but not as is.  Starlink requires a dedicated manufacturing facility and launch resources just to keep up with the replacement rate.  The first world wide Mars system will need to be geostationary.
Not "geo"stationary, it would be areostationary. I vehemently disagree.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Swedish chef on 11/09/2019 03:02 pm
The exact details escape me but I have many questions. Point me towards a better thread and I would love to hash it out.

Perhaps this thread? (SpX Mars Communication Constellation?)
https://forum.nasaspaceflight.com/index.php?topic=45483.0
Title: Re: Starlink : General Discussion - Thread 2
Post by: OTV Booster on 11/09/2019 07:00 pm
So it occurs to me to wonder, will this be the first product that Musk actively advertises to the general public? For all his reputation for PR stunts, neither Falcon 9s nor Teslas are advertised in the "buying ad time in various media" manner.

I'm thinking they are not going to be able to depend on word of mouth for Starlink, and are going to have to resort to traditional advertising -- commercials, banners, direct mailings, the whole shebang.

Going to be interesting to see what they come up with.

Given how outraged so many are with local monopoly ISP’s taking a customer service page from THE PHONE COMPANY, it shouldn’t be that hard a sell.

I’m posting from a coffee shop with WIFI. Offer coffee shops and like locations a good up front deal and require a small poster and handouts and word of mouth will take off. Do some sort of freebie or low cost service to schools and libraries and the instant gratification of word of mouth won’t happen but a deeper appreciation will grow.

Just don’t let it become THE PHONE COMPANY and it will grow quickly.

Phil
Title: Re: Starlink : General Discussion - Thread 2
Post by: Mandella on 11/09/2019 07:44 pm
So it occurs to me to wonder, will this be the first product that Musk actively advertises to the general public? For all his reputation for PR stunts, neither Falcon 9s nor Teslas are advertised in the "buying ad time in various media" manner.

I'm thinking they are not going to be able to depend on word of mouth for Starlink, and are going to have to resort to traditional advertising -- commercials, banners, direct mailings, the whole shebang.

Going to be interesting to see what they come up with.

Does door to door at SolarCity count?

I had actually forgotten about SolarCity. I personally haven't seen an ad for them, but then I'm not in their covered region either. Do they go door to door now after the acquisition?

I should note that I am not expressly against advertising, just wondering what form it will take for Starlink. And I think they need more market penetration and speedy buildup than one can get from door to door. Not that it matters much for me. Seeing as that I am pretty much the exact target market for Starlink I'll be signing up as soon as I can get on the waiting list, so no advertising required.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Cherokee43v6 on 11/09/2019 08:01 pm
So it occurs to me to wonder, will this be the first product that Musk actively advertises to the general public? For all his reputation for PR stunts, neither Falcon 9s nor Teslas are advertised in the "buying ad time in various media" manner.

I'm thinking they are not going to be able to depend on word of mouth for Starlink, and are going to have to resort to traditional advertising -- commercials, banners, direct mailings, the whole shebang.

Going to be interesting to see what they come up with.

Does door to door at SolarCity count?

I had actually forgotten about SolarCity. I personally haven't seen an ad for them, but then I'm not in their covered region either. Do they go door to door now after the acquisition?

I should note that I am not expressly against advertising, just wondering what form it will take for Starlink. And I think they need more market penetration and speedy buildup than one can get from door to door. Not that it matters much for me. Seeing as that I am pretty much the exact target market for Starlink I'll be signing up as soon as I can get on the waiting list, so no advertising required.

Solar City got rolled into Tesla a couple years ago as I recall.  The Tesla 'Power Wall' was originally to be a Solar City product.

As to Starlink, they'll probably roll it out first as a link to Tesla cars (for updates and such) then start marketing it as a consumer service.  This will enable them to debug operations in a live environment before making paying customers mad.
Title: Re: Starlink : General Discussion - Thread 2
Post by: RedLineTrain on 11/09/2019 09:24 pm
Starlink user terminals are not suitable for a direct connection to Tesla cars.  Maybe sometime down the road, SpaceX will do the development work necessary to make such a connection.  In the meantime, there's opportunity to connect superchargers and service centers, and the like.  But the opportunity is not huge.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Eka on 11/09/2019 11:44 pm
Possible customers:
Hotels/motels, especially rural ones.
Rural homes
Coffee shops
restaurants
Malls
Small phone companies
Apartment buildings/complexes
Office buildings
manufacturing plants
remote cameras
any corporation's remote facilities
Obviously aircraft and cruise ships.
Intercity coaches.
Truckers for mandated down time.
RVers, especially full timers.

On rural homes. I actually have great service from my rural phone company. I have fiber to the farm, and can watch 2 4K video streams over it with the base package. 10 miles east of me, nope. Only choices are satellite services for nearly twice as much. The only reason I have such good service is my phone company got federal grants to put it in.
Title: Re: Starlink : General Discussion - Thread 2
Post by: OTV Booster on 11/10/2019 12:15 am
I think about Starlink's future and I believe that Starlink could be use as a constellation for Mars internet. When we talk about multiplanetary humanity, we have to think that human need various device on the place they live. Those needs could be internet and high speed communication on Mars.

What you think about that ?

This has been discussed many times.

My personal take is that it is a no brainer but...

The first crewed landing will have to concentrate on immediate survival infrastructure. There may be preliminary exploration away from the main base but again only opinion, nothing more than a few days away.

The second and subsequent missions will range further, but probably all within the hemisphere. A single Aresynchronis sat is (I think) the easiest and least resource intensive solution for basic comms and instrumentation. This will do for at least three synods. If you have a heavy gaming habit early Mars is probably not a good idea.

There will be a constellation in its turn. More pressing will be high bandwidth Mars-Earth comms even when Earth is hidden by the sun.

Phil

Edit to add: on rethink, requirements for mars orbit are very different than an areobrake landing. IIUC it might actually takes more fuel, but one large synchronous sat would surely be an underwhelming load. There could be a passle of starlinks too.

I think SS is supposed to carry 400 starlinks. If the big sat makes up half the load and the starlinks need to be more robust (for many reasons) there might still be 150 delivered. Adjust numbers as required.

They will need orbits very different than the big sat. I am not capable of running the numbers. Maybe the SS would still have enough dV to deliver, maybe the sats own on board thrusters could get them there.

If run at earth altitudes the coverage would suck but there is no Van Allen belt so they can be higher. It’s not like they’ll have all that many customers.

So why run the big sat at all? Belt & suspenders. Once more starlinks are on line it’s redundant.
Title: Re: Starlink : General Discussion - Thread 2
Post by: high road on 11/10/2019 10:15 am

Is there a way to know when the line of Starlink satellites will pass overhead? So a map with the trajectory and time after launch, or somesuch? I'd love to see that with my own eyes. Considering I live in an area with extensive artificial lighting, my chances to discern anything are pretty low, so I'd love to at least know when I should be looking.
Title: Re: Starlink : General Discussion - Thread 2
Post by: rsdavis9 on 11/10/2019 01:18 pm

Is there a way to know when the line of Starlink satellites will pass overhead? So a map with the trajectory and time after launch, or somesuch? I'd love to see that with my own eyes. Considering I live in an area with extensive artificial lighting, my chances to discern anything are pretty low, so I'd love to at least know when I should be looking.

Heavensabove is a good site. There are many others.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 11/10/2019 02:19 pm

Is there a way to know when the line of Starlink satellites will pass overhead? So a map with the trajectory and time after launch, or somesuch? I'd love to see that with my own eyes. Considering I live in an area with extensive artificial lighting, my chances to discern anything are pretty low, so I'd love to at least know when I should be looking.

Heavensabove is a good site. There are many others.

We have a separate thread for discussion of spotting the satellites:
Starlink Satellite Spotting (https://forum.nasaspaceflight.com/index.php?topic=47030.0)
Title: Re: Starlink : General Discussion - Thread 2
Post by: high road on 11/10/2019 02:24 pm
Thx.
Title: Re: Starlink : General Discussion - Thread 2
Post by: sevenperforce on 11/11/2019 03:16 pm
I've been thread-hunting for this but haven't found the discussion yet -- what is the deployment mechanism for these? Whatever it is, it's brilliant. They mentioned a "tensioner release" on the webcast today but I am just very curious if anyone has an idea how it works.
Title: Re: Starlink : General Discussion - Thread 2
Post by: eriblo on 11/11/2019 03:40 pm
I've been thread-hunting for this but haven't found the discussion yet -- what is the deployment mechanism for these? Whatever it is, it's brilliant. They mentioned a "tensioner release" on the webcast today but I am just very curious if anyone has an idea how it works.
Each Starlink has three cylindrical mounting points which insert slightly into the next one in the stack preventing sideways motion (they are stacked two side by side 30 sats high). Four tension rods span the whole stack and keeps it in compression. Second stage starts rotating perpendicular to the long axis and the tension rods are released so that the stack separates due to different tangential velocities.

Analogy: grab a deck of cards along the sides from above, make a gentle sweeping motion and release. Cards everywhere...
Title: Re: Starlink : General Discussion - Thread 2
Post by: sevenperforce on 11/11/2019 04:06 pm
Anyone know how they plan to unload the reaction control wheels?
Title: Re: Starlink : General Discussion - Thread 2
Post by: rsdavis9 on 11/11/2019 04:08 pm
Anyone know how they plan to unload the reaction control wheels?

Hall thrusters with krypton
Title: Re: Starlink : General Discussion - Thread 2
Post by: sevenperforce on 11/11/2019 04:12 pm
Anyone know how they plan to unload the reaction control wheels?

Hall thrusters with krypton
Ah, I didn't realize they had enough of them.
Title: Re: Starlink : General Discussion - Thread 2
Post by: eriblo on 11/11/2019 05:54 pm
Anyone know how they plan to unload the reaction control wheels?

Hall thrusters with krypton
Ah, I didn't realize they had enough of them.
https://twitter.com/elonmusk/status/1132906066423889920
Tweet contents: Q: Do the #Starlink solar panels rotate or are they fixed?
Are these moment control gyros and, if so, how do you desaturate them?
Elon: Rotate on one axis. Magnetic torque rods for desaturation of momentum wheels.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Asteroza on 11/11/2019 11:03 pm
I've been thread-hunting for this but haven't found the discussion yet -- what is the deployment mechanism for these? Whatever it is, it's brilliant. They mentioned a "tensioner release" on the webcast today but I am just very curious if anyone has an idea how it works.
Each Starlink has three cylindrical mounting points which insert slightly into the next one in the stack preventing sideways motion (they are stacked two side by side 30 sats high). Four tension rods span the whole stack and keeps it in compression. Second stage starts rotating perpendicular to the long axis and the tension rods are released so that the stack separates due to different tangential velocities.

Analogy: grab a deck of cards along the sides from above, make a gentle sweeping motion and release. Cards everywhere...

So the 4 rods end up being ejected debris then? The last launch had 4 unidentifieds slowly deorbiting that would fit the description.
Title: Re: Starlink : General Discussion - Thread 2
Post by: RoboGoofers on 11/12/2019 04:25 pm
Seeing as the starlink hardware is pretty small/lightweight, can it be installed in planes and ships to act as bent-pipe relay stations?

in other words, instead of just end user terminals planes could have the same hardware as the sats (minus all the satellite specific stuff)? remove the aluminum structure, batteries, reaction wheels, thrusters and solar panels and a rough guess would be there's about 50-100 kg of network hardware and antennas so certainly not a major burden to a passenger airplane.

That would help with not having the ISL yet (though they'll be on there long before there's a airline ready to deploy starlink hardware on planes)
Title: Re: Starlink : General Discussion - Thread 2
Post by: ThomasGadd on 11/12/2019 04:35 pm
Seeing as the starlink hardware is pretty small/lightweight, can it be installed in planes and ships to act as bent-pipe relay stations?

in other words, instead of just end user terminals planes could have the same hardware as the sats (minus all the satellite specific stuff)?

Sure that would work for testing.  The ISL's are suppose to be operational next year.
Title: Re: Starlink : General Discussion - Thread 2
Post by: rsdavis9 on 11/12/2019 04:43 pm
I've been thread-hunting for this but haven't found the discussion yet -- what is the deployment mechanism for these? Whatever it is, it's brilliant. They mentioned a "tensioner release" on the webcast today but I am just very curious if anyone has an idea how it works.
Each Starlink has three cylindrical mounting points which insert slightly into the next one in the stack preventing sideways motion (they are stacked two side by side 30 sats high). Four tension rods span the whole stack and keeps it in compression. Second stage starts rotating perpendicular to the long axis and the tension rods are released so that the stack separates due to different tangential velocities.

Analogy: grab a deck of cards along the sides from above, make a gentle sweeping motion and release. Cards everywhere...

So the 4 rods end up being ejected debris then? The last launch had 4 unidentifieds slowly deorbiting that would fit the description.

Couldn't they make these rods out of composite so they burn up better and reenter faster? Maybe attach a small sail to the end of a rod to reenter sooner?
Title: Re: Starlink : General Discussion - Thread 2
Post by: whitelancer64 on 11/12/2019 05:00 pm
I've been thread-hunting for this but haven't found the discussion yet -- what is the deployment mechanism for these? Whatever it is, it's brilliant. They mentioned a "tensioner release" on the webcast today but I am just very curious if anyone has an idea how it works.
Each Starlink has three cylindrical mounting points which insert slightly into the next one in the stack preventing sideways motion (they are stacked two side by side 30 sats high). Four tension rods span the whole stack and keeps it in compression. Second stage starts rotating perpendicular to the long axis and the tension rods are released so that the stack separates due to different tangential velocities.

Analogy: grab a deck of cards along the sides from above, make a gentle sweeping motion and release. Cards everywhere...

So the 4 rods end up being ejected debris then? The last launch had 4 unidentifieds slowly deorbiting that would fit the description.

Couldn't they make these rods out of composite so they burn up better and reenter faster? Maybe attach a small sail to the end of a rod to reenter sooner?

Why not composite? Cost. Why no "sail"? That would be another thing that needs to deploy, needs power, etc. so Complexity. Also - Weight. Both of which feed into Cost.
Title: Re: Starlink : General Discussion - Thread 2
Post by: deadman719 on 11/12/2019 10:23 pm
I've been thread-hunting for this but haven't found the discussion yet -- what is the deployment mechanism for these? Whatever it is, it's brilliant. They mentioned a "tensioner release" on the webcast today but I am just very curious if anyone has an idea how it works.
Each Starlink has three cylindrical mounting points which insert slightly into the next one in the stack preventing sideways motion (they are stacked two side by side 30 sats high). Four tension rods span the whole stack and keeps it in compression. Second stage starts rotating perpendicular to the long axis and the tension rods are released so that the stack separates due to different tangential velocities.

Analogy: grab a deck of cards along the sides from above, make a gentle sweeping motion and release. Cards everywhere...

So the 4 rods end up being ejected debris then? The last launch had 4 unidentifieds slowly deorbiting that would fit the description.

One of the rods can be seen in the attached screen shot captured from the webcast.

Respectfully,
Rob
Title: Re: Starlink : General Discussion - Thread 2
Post by: su27k on 11/13/2019 03:22 am
SpaceX's next Starlink launch will make it one of the top satellite operators in the world (https://www.floridatoday.com/story/tech/science/space/2019/11/08/spacex-next-starlink-launch-make-one-top-satellite-operators-cape-canaveral-florida/2530064001/)

Note this refers to the launch that just happened.

Quote
According to the Space Foundation, a nonprofit based in Colorado that advocates for space industries around the world, the launch will propel SpaceX to the No. 2 position from a number-on-orbit standpoint:

* Planet: 197 Earth observation satellites
* SpaceX: 120 internet-beaming satellites (117 after contact was lost with three in May; expected to deorbit and burn up)
* Iridium: 106 communications satellites
* Air Force: A mix of 98 classified, communications, Earth observation, position and navigation, and technology development satellites
* Spire: 85 Earth observation satellites
* NASA: 67 science, Earth science, technology development, and communications satellites (includes International Space Station)

With just two more Starlink launches, scheduled to happen by next year, SpaceX will eclipse Planet to become the No. 1 operator by volume.
Title: Re: Starlink : General Discussion - Thread 2
Post by: su27k on 11/13/2019 03:27 am
I mean this news may be interesting - 10 minutes ago I received mail:
//Dear valued LeoSat Partner,  We very much appreciate your interest and commitment to LeoSat and with this letter I would like to update you on the latest developments.
LeoSat as a NewSpace company is confronted with the same challenges of any start-up that is moving along the evolution from vision to reality. Whilst the company maintains its strong vision as a unique solution for B2B data connectivity in LEO, validated by the market and our early investors, we are now facing critical funding issues.  Late last week we had to make the very difficult decision to cancel our early obtained FCC license that required a long term financial commitment equal to that of multiple FTEs. As a startup we could no longer justify carrying the cost this early in the project and we will reapply for this license closer to launch, in parallel to obtaining our licenses in other countries.
//

Starlink will have minus one competitor  and more interest from investors

Seems LeoSat is gone now: Satellite broadband constellation startup LeoSat ends hunt for investors, shuts down; Thales Ka-band ITU filing at risk (https://www.spaceintelreport.com/satellite-broadband-constellation-startup-leosat-ends-hunt-for-investors-shuts-down-thales-ka-band-itu-filing-at-risk/)

The article is behind a paywall, only the following excerpt is available:

Quote
Credit: LeoSat PARIS — Startup satellite broadband B2B provider LeoSat has suspended operations — which in recent months has mainly consisted of looking for investors — and
Title: Re: Starlink : General Discussion - Thread 2
Post by: RocketGoBoom on 11/14/2019 01:00 am
With all of the news recently about C band alliance (Intelsat, SES and Telesat) having to share their C band spectrum with 5G mobile providers, it got me to wondering why Ku band spectrum is free for satellite providers, but spectrum for cell phone providers is auctioned and they have to pay crazy amounts of money for it.

Can someone explain it to me as if I am 5th grader?

From reading the articles about it, the C band alliance of satellite companies (Intelsat, SES and Telesat) didn't have to pay for the C band spectrum that they have been using for decades. But now that the writing is on the wall that they have to share that spectrum, at least in the USA region, they want to manage the auction and keep 80% of the money, only giving 20% to the US government.

All of their stocks tanked today by huge amounts, based I think upon the realization of the stock market that the US government is probably not going to let them keep the money from the auction.

Why doesn't anyone have to pay for the rights to the Ku spectrum that most satellites use? Why aren't SpaceX and OneWeb bidding for the spectrum they want? I am sure it would be insanely complex since it is spectrum technically covering every country on the planet. But that has never stopped countries from doing a tax grab in the past.

My understanding of all of this is at a very basic level, meaning I just read SpaceNews and a few other articles about the topics. But none of them dive into the details explaining this.

Thanks in advance for any explanations.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Rondaz on 11/16/2019 05:14 pm
Here's something interesting. Back in July, two @SpaceX #Starlink satellites changed their orbits and manoeuvred close to each other. The closest approach was on July 21st, when around 18:32UT the distance was only 80 meters!

https://twitter.com/cgbassa/status/1195754992797454336
Title: Re: Starlink : General Discussion - Thread 2
Post by: FutureSpaceTourist on 11/16/2019 05:16 pm
Edit: ninja’d! Whole thread is worth a read

Sorry, not up to date with this thread - so apologies if this is old news

https://twitter.com/cgbassa/status/1195754992797454336

Quote
Here's something interesting. Back in July, two @SpaceX #Starlink satellites changed their orbits and manoeuvred close to each other. The closest approach was on July 21st, when around 18:32UT the distance was only 80 meters! What was going on here @elonmusk?

twitter.com/cgbassa/status/1195755002121408513

Quote
The two #Starlink satellites were Starlink-67 [44278/19029AV] and Starlink-46 [44246/19029M]. Shortly after launch, the orbit of Starlink-67 was lowered to 400 km, supposedly to demonstrate re-entry. Starlink-46 had manoeuvred to the operational altitude of 550km.

https://twitter.com/cgbassa/status/1195755004034002946

Quote
Around mid-July, both satellites actively manoeuvred away from those orbits to initiate the close approach by matching their orbital planes and altitudes. Between July 21 and 24, they stayed well within 40 km from each other, with two very close approaches of 100 m on July 21st.

twitter.com/cgbassa/status/1195755005363572739

Quote
After these 3 days, Starlink-46 raised its orbit and moved away from Starlink-67. Later on both satellites further changed their orbits, so both were still active at that time. (On September 2, Starlink-67 nearly collided with @ESA's #Aeolus satellite.) twitter.com/esaoperations/…

https://twitter.com/cgbassa/status/1195755006936453123

Quote
These close approaches between Starlink-46 and 67 suggest that one inspected the other. This raises a host of questions... Why was an inspection needed? What sensors do #Starlink satellites have that makes it worthwhile to move an operational satellite for this inspection?

https://twitter.com/cgbassa/status/1195755008320573446

Quote
What is special about Starlink-46? Why did is it the only one that lowered its orbit? Do either Starlink-46 or 67 have enough fuel to either move back to operational altitude, or actively de-orbit themselves? Why did @SpaceX not publicize this close encounter? (Did I miss it?)

https://twitter.com/cgbassa/status/1195755009583067138

Quote
These calculations use publicly available orbital elements of #Starlink satellites. They are available at @SpaceTrackOrg and at @TSKelso's celestrak.com. I'd be interested in confirmation of my calculations. @planet4589 @Marco_Langbroek @cosmos4u @Astro_Jonny
Title: Re: Starlink : General Discussion - Thread 2
Post by: abaddon on 11/16/2019 05:19 pm
Very interesting stuff.  Throwing my hat into the ring, I'm going to guess that they were testing collision avoidance sensors and autonomous collision avoidance systems.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Nomadd on 11/16/2019 05:50 pm
Very interesting stuff.  Throwing my hat into the ring, I'm going to guess that they were testing collision avoidance sensors and autonomous collision avoidance systems.
Maybe testing the ability of a retiring satellite to deorbit a defective one.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Herb Schaltegger on 11/16/2019 10:01 pm
I'd be leery of this analysis until there's more info available about the data used to indicate some kind of rendezvous, intentional or otherwise. Unless the satellite vehicles were observed in real-time or actively-tracked via Doppler or something, inferring orbital precise orbital maneuvers using public TLEs is fraught; TLEs aren't always updated in a timely manner; they've always got some degree of uncertainty or error bands even for non-maneuvering vehicles; and with dozens of separate objects being tracked, some sets of data will be more accurate than other from day to day and vehicle to vehicle.
Title: Re: Starlink : General Discussion - Thread 2
Post by: RedLineTrain on 11/16/2019 10:52 pm
I am reading "Eccentric Orbits:  The Iridium Story."  Very interesting and topical.  It has a lot of stuff -- mainly business and marketing -- that's applicable to Starlink.

SpaceX's approach is almost opposite of the original Iridium.

1.  Starlink is first being rolled out in the "easy" regulatory geographies, whereas Iridium had a worldwide release.
2.  SpaceX is spending zero on marketing and advertising, whereas Iridium spent hundreds of millions of dollars.
3.  SpaceX is avoiding business entanglements where possible, whereas Iridium sought them out in order to get regulatory buy-in from other countries.
4.  Starlink is owned 100% by SpaceX whereas Iridium was publicly-traded as a separate entity to Motorola.
5.  Starlink does not have to do contortions to enrich the parent company, whereas Iridium had a huge monthly service contract with Motorola.
6.  Starlink is being funded almost entirely by equity, whereas Iridium was majority funded by debt.
7.  Starlink investment is being done in stages, whereas Iridium was a single shot.

It seems that OneWeb is falling into some of the same traps as Iridium, and that's why you're seeing lawsuits and the like.  Perhaps Softbank's continued investment has pulled them back from doing too much of that.  It's apparent that for a few years, OneWeb was having difficulty raising capital, but maybe that has changed.

But even though SpaceX is not falling into the same traps, perhaps it is falling into others that we don't know about.  This is just a challenging business.  For instance, I wonder whether Starlink will ever be introduced into some parts of Europe for reasons unrelated to technological fitness.
Title: Re: Starlink : General Discussion - Thread 2
Post by: docmordrid on 11/16/2019 11:10 pm
>
 For instance, I wonder whether Starlink will ever be introduced into some parts of Europe for reasons unrelated to technological fitness.

If DoD becomes an anchor tenant much of NATO will follow. Then it becomes a question of commercial customers being allowed to use StarLink by protectionist minded local govts..
Title: Re: Starlink : General Discussion - Thread 2
Post by: RedLineTrain on 11/16/2019 11:21 pm
>
 For instance, I wonder whether Starlink will ever be introduced into some parts of Europe for reasons unrelated to technological fitness.

If DoD becomes an anchor tenant much of NATO will follow. Then it becomes a question of commercial customers being allowed to use StarLink by protectionist minded local govts..

I agree that DoD is a key customer.  At this point, SpaceX is assuming the risk with the FCC that there will be complications with the ITU.  But if it's a matter of national security, SpaceX will probably be able to tell the ITU to pound sand, should the need arise, and it will all be worked out satisfactorily to SpaceX.

It was great to see the report of 610 megabit downloads into the cockpit of a C-12J Huron.  I will be interested in seeing whether the newly-launched Ka-band satellites will be able to push that over a gigabit.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 11/16/2019 11:26 pm
It was great to see the report of 610 megabit downloads into the cockpit of a C-12J Huron.  I will be interested in seeing whether the newly-launched Ka-band satellites will be able to push that over a terabit.

Megabit to terabit is a pretty big jump...
Title: Re: Starlink : General Discussion - Thread 2
Post by: RedLineTrain on 11/16/2019 11:27 pm
Oops.  Yes, I will correct!  :D
Title: Re: Starlink : General Discussion - Thread 2
Post by: Eka on 11/16/2019 11:44 pm
>
 For instance, I wonder whether Starlink will ever be introduced into some parts of Europe for reasons unrelated to technological fitness.

If DoD becomes an anchor tenant much of NATO will follow. Then it becomes a question of commercial customers being allowed to use StarLink by protectionist minded local govts..

I agree that DoD is a key customer.  At this point, SpaceX is assuming the risk with the FCC that there will be complications with the ITU.  But if it's a matter of national security, SpaceX will probably be able to tell the ITU to pound sand, should the need arise, and it will all be worked out satisfactorily to SpaceX.

It was great to see the report of 610 megabit downloads into the cockpit of a C-12J Huron.  I will be interested in seeing whether the newly-launched Ka-band satellites will be able to push that over a gigabit.
I don't know if it was EM or GS that said the new batch have 4X the data transfer throughput of the previous ones. Of course what wasn't mentioned was if that was per beam or overall throughput.
Title: Re: Starlink : General Discussion - Thread 2
Post by: FutureSpaceTourist on 11/17/2019 07:34 pm
twitter.com/harrystoltz1/status/1196137767673069568

Quote
Great visualization of #Starlink’s new orbits!

https://twitter.com/harrystoltz1/status/1196137767673069568

Quote
Animation: reddit.com/r/Starlink/com…
Check it out for yourself: celestrak.com/cesium/orbit-v…
Title: Re: Starlink : General Discussion - Thread 2
Post by: niwax on 11/17/2019 08:57 pm
Graph from r/starlink:

(https://i.imgur.com/ObTMTIz.png)

The satellites might reach their final orbit within a month.

Great to see the debris seems to be coming down around 0.5km/day. That might mean full reentry within a few months. Incredible how much stronger the atmosphere is at that altitude compared to the last Starlink launch. Definitely a big improvement and an example other constellations should follow.

Fun fact: The debris is coming down at literally a snails pace right now.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 11/18/2019 04:03 pm
For discussion about the impact of satellites on astronomy we are using the following thread:
Impacts of Large Satellite Constellations on Astronomy (https://forum.nasaspaceflight.com/index.php?topic=48302.0)
Title: Re: Starlink : General Discussion - Thread 2
Post by: Texsun on 11/21/2019 04:45 pm

These things matter. There are hard costs and limited funds. People shouldn't forget that.

Regarding financing for Starship, one word...

                                                                                   Starlink

If that progresses as planned, SpaceX will not have issues with financing going forward and optics will be less of an issue.
Title: Re: Starlink : General Discussion - Thread 2
Post by: jpo234 on 11/21/2019 04:50 pm

These things matter. There are hard costs and limited funds. People shouldn't forget that.

Regarding financing for Starship, one word...

                                                                                   Starlink

If that progresses as planned, SpaceX will not have issues with financing going forward and optics will be less of an issue.

Chicken and egg: They need Starship in the not too distant future to launch the bulk of the Starlink satellites.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Nibb31 on 11/21/2019 06:04 pm

These things matter. There are hard costs and limited funds. People shouldn't forget that.

Regarding financing for Starship, one word...

                                                                                   Starlink

If that progresses as planned, SpaceX will not have issues with financing going forward and optics will be less of an issue.
Starlink (and other constellations) will have to fight against 5G and well-established conventional network providers with deep pockets and strong political support. They are not going to go down without a fight.
LEO constellations have an edge when it comes to niche markets like airline and naval broadband and developing countries, but that's not where the Mars colony kind of money is.
Title: Re: Starlink : General Discussion - Thread 2
Post by: sferrin on 11/21/2019 06:18 pm

These things matter. There are hard costs and limited funds. People shouldn't forget that.

Regarding financing for Starship, one word...

                                                                                   Starlink

If that progresses as planned, SpaceX will not have issues with financing going forward and optics will be less of an issue.
Starlink (and other constellations) will have to fight against 5G and well-established conventional network providers with deep pockets and strong political support. They are not going to go down without a fight.
LEO constellations have an edge when it comes to niche markets like airline and naval broadband and developing countries, but that's not where the Mars colony kind of money is.

5G has a giant black eye (in the US anyway) due to the China/Huawei fiasco.
Title: Re: Starlink : General Discussion - Thread 2
Post by: rsdavis9 on 11/21/2019 06:20 pm

These things matter. There are hard costs and limited funds. People shouldn't forget that.

Regarding financing for Starship, one word...

                                                                                   Starlink

If that progresses as planned, SpaceX will not have issues with financing going forward and optics will be less of an issue.
Starlink (and other constellations) will have to fight against 5G and well-established conventional network providers with deep pockets and strong political support. They are not going to go down without a fight.
LEO constellations have an edge when it comes to niche markets like airline and naval broadband and developing countries, but that's not where the Mars colony kind of money is.

You forgot remote locations in the CONUS.
Anybody know how big that is?
I know personally of 2 people with that need.
Southwest NH
Chico TX
Title: Re: Starlink : General Discussion - Thread 2
Post by: Texsun on 11/21/2019 06:49 pm
Starlink (and other constellations) will have to fight against 5G and well-established conventional network providers with deep pockets and strong political support. They are not going to go down without a fight.
LEO constellations have an edge when it comes to niche markets like airline and naval broadband and developing countries, but that's not where the Mars colony kind of money is.

As a rural Texas resident with ridiculously expensive choices for home internet, I disagree. There are no conventional network providers at all among my choices. A local telephone coop 5mbs @$90/mo, a rural wireless broadband service offering 3mbs down-1mbs up @$80/mo, and cell phone data (which is sketchy, but what I use now).

There will be plenty of domestic users of Starkink, supporting OCCUPY MARS with every key stroke. If nothing else, it will force the status quo to become competitive price-wise for their urban users. As well as provide new startup providers a source of service to distribute at a lower rate. It has been a long time coming, but SpaceX will level the playing field in this department and I suspect adoption will generate significant income for Starship development.
Title: Re: Starlink : General Discussion - Thread 2
Post by: docmordrid on 11/21/2019 07:10 pm

These things matter. There are hard costs and limited funds. People shouldn't forget that.

Regarding financing for Starship, one word...

                                                                                   Starlink

If that progresses as planned, SpaceX will not have issues with financing going forward and optics will be less of an issue.

Chicken and egg: They need Starship in the not too distant future to launch the bulk of the Starlink satellites.

But they can launch enough of StarLink to get revenue positive using Falcon 9.
Title: Re: Starlink : General Discussion - Thread 2
Post by: ncb1397 on 11/21/2019 07:16 pm

These things matter. There are hard costs and limited funds. People shouldn't forget that.

Regarding financing for Starship, one word...

                                                                                   Starlink

If that progresses as planned, SpaceX will not have issues with financing going forward and optics will be less of an issue.
Starlink (and other constellations) will have to fight against 5G and well-established conventional network providers with deep pockets and strong political support. They are not going to go down without a fight.
LEO constellations have an edge when it comes to niche markets like airline and naval broadband and developing countries, but that's not where the Mars colony kind of money is.

5G has a giant black eye (in the US anyway) due to the China/Huawei fiasco.

Exactly the opposite. U.S. carriers aren't using Huawei 5G.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Nibb31 on 11/21/2019 07:24 pm

These things matter. There are hard costs and limited funds. People shouldn't forget that.

Regarding financing for Starship, one word...

                                                                                   Starlink

If that progresses as planned, SpaceX will not have issues with financing going forward and optics will be less of an issue.
Starlink (and other constellations) will have to fight against 5G and well-established conventional network providers with deep pockets and strong political support. They are not going to go down without a fight.
LEO constellations have an edge when it comes to niche markets like airline and naval broadband and developing countries, but that's not where the Mars colony kind of money is.

5G has a giant black eye (in the US anyway) due to the China/Huawei fiasco.
All US operators are investing heavily in 5G deployment as we speak.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Texsun on 11/21/2019 07:52 pm
All US operators are investing heavily in 5G deployment as we speak.

SpaceX can put 60 new satellites into LEO in less than an hour. Deployed to their orbits in a week or so. I've been waiting for any Cell phone company to provide me uninterrupted phone service in the 25 minute drive between home and work for decades.

5G deployment will be focused on upgrading existing infrastructure for customers in urban areas. That leaves a tremendous opportunity for Starlink to reap more than enough of the gravy spilling off the plate by providing Internet services to those areas the phone/internet companies won't invest in infrastructure at all.

The military and government contracts, as well as the rest of the world currently without affordable Internet access will offer enough gravy to smother the meat and potatoes that are the Starship Projects (9m, 18m, etc.).

This economy of scale provides a huge potential income without having to take any existing customer's business from the most significant providers. (though I suspect that it could)

7.7 billion on the planet. Let's lowball it and say 10% are "rural." Let's lowball once more and say 10% of those subscribe to Starlink. After expenses, let's lowball it again and say that each of these subscribers only generate $1/month profit for SpaceX. These are all very conservative numbers. This results in about 1 Billion per year. If they make $2/mo/customer, that's 2 Billion per year.

Moon and Mars colonization could be primarily funded by the rural populations of planet Earth coming online.
Title: Re: Starlink : General Discussion - Thread 2
Post by: mwfair on 11/21/2019 08:00 pm
All US operators are investing heavily in 5G deployment as we speak.
OT. 
edit: removed snark
Title: Re: Starlink : General Discussion - Thread 2
Post by: AC in NC on 11/21/2019 08:36 pm
Carve-over from Texas Prototype Discussion

Starlink (and other constellations) will have to fight against 5G and well-established conventional network providers with deep pockets and strong political support. They are not going to go down without a fight.
LEO constellations have an edge when it comes to niche markets like airline and naval broadband and developing countries, but that's not where the Mars colony kind of money is.

As a rural Texas resident with ridiculously expensive choices for home internet, I disagree. There are no conventional network providers at all among my choices. A local telephone coop 5mbs @$90/mo, a rural wireless broadband service offering 3mbs down-1mbs up @$80/mo, and cell phone data (which is sketchy, but what I use now).

Heck, I've got solid service at regular 100 MByte/s download for $65 and will jump on Starlink to kick the tires as soon as I can simply because of what it supports.   

But as with your situation, there are plenty of folks even in moderately populated areas here that don't have great options.  My parents within 20 mins of a major city have weak DSL and 1-bar 4G.  There is a lot of untapped rural market potential.
Title: Re: Starlink : General Discussion - Thread 2
Post by: envy887 on 11/21/2019 08:45 pm
Carve-over from Texas Prototype Discussion

Starlink (and other constellations) will have to fight against 5G and well-established conventional network providers with deep pockets and strong political support. They are not going to go down without a fight.
LEO constellations have an edge when it comes to niche markets like airline and naval broadband and developing countries, but that's not where the Mars colony kind of money is.

As a rural Texas resident with ridiculously expensive choices for home internet, I disagree. There are no conventional network providers at all among my choices. A local telephone coop 5mbs @$90/mo, a rural wireless broadband service offering 3mbs down-1mbs up @$80/mo, and cell phone data (which is sketchy, but what I use now).

Heck, I've got solid service at regular 100 MByte/s download for $65 and will jump on Starlink to kick the tires as soon as I can simply because of what it supports.   

But as with your situation, there are plenty of folks even in moderately populated areas here that don't have great options.  My parents within 20 mins of a major city have weak DSL and 1-bar 4G.  There is a lot of untapped rural market potential.

Same to a tee...
Title: Re: Starlink : General Discussion - Thread 2
Post by: GregTheGrumpy on 11/21/2019 09:16 pm
Starlink (and other constellations) will have to fight against 5G and well-established conventional network providers with deep pockets and strong political support. They are not going to go down without a fight.
LEO constellations have an edge when it comes to niche markets like airline and naval broadband and developing countries, but that's not where the Mars colony kind of money is.

As a rural Texas resident with ridiculously expensive choices for home internet, I disagree. There are no conventional network providers at all among my choices. A local telephone coop 5mbs @$90/mo, a rural wireless broadband service offering 3mbs down-1mbs up @$80/mo, and cell phone data (which is sketchy, but what I use now).

There will be plenty of domestic users of Starkink, supporting OCCUPY MARS with every key stroke. If nothing else, it will force the status quo to become competitive price-wise for their urban users. As well as provide new startup providers a source of service to distribute at a lower rate. It has been a long time coming, but SpaceX will level the playing field in this department and I suspect adoption will generate significant income for Starship development.

When I read the inner quote, I said to myself,  "South Texas must be a developing area."  Some of my customers can't even get cell coverage and must depend on satellite service.  It stinks and I, for one, am eagerly waiting until I can buy (and recommend) Starlink service.  Perhaps as early as next year.  I am quite positive there are other rural areas across the USA and other places that just don't have much in the way of options.
Title: Re: Starlink : General Discussion - Thread 2
Post by: niwax on 11/21/2019 09:48 pm
Carve-over from Texas Prototype Discussion

Starlink (and other constellations) will have to fight against 5G and well-established conventional network providers with deep pockets and strong political support. They are not going to go down without a fight.
LEO constellations have an edge when it comes to niche markets like airline and naval broadband and developing countries, but that's not where the Mars colony kind of money is.

As a rural Texas resident with ridiculously expensive choices for home internet, I disagree. There are no conventional network providers at all among my choices. A local telephone coop 5mbs @$90/mo, a rural wireless broadband service offering 3mbs down-1mbs up @$80/mo, and cell phone data (which is sketchy, but what I use now).

Heck, I've got solid service at regular 100 MByte/s download for $65 and will jump on Starlink to kick the tires as soon as I can simply because of what it supports.   

But as with your situation, there are plenty of folks even in moderately populated areas here that don't have great options.  My parents within 20 mins of a major city have weak DSL and 1-bar 4G.  There is a lot of untapped rural market potential.

Ultimately, a 4G antenna has to run off the same backbone as your internet connection. No broadband, no 4G. In those cases, Starlink actually empowers 4G providers instead of competing with them. I have toyed with the idea of a fully integrated cell tower and Starlink receiver for a while. If you manage to pack both in a box, maybe even with a small battery and solar panels, expanding a 4G network becomes dropping off $5000 boxes every mile or so.

The idea could carry even further than the still-bad cell networks in the developed world. Want to connect a million people in rural Africa to the internet? Drop a handful of boxes in every village you can find. Need to connect a camp site or research station? Well, guess what...
Title: Re: Starlink : General Discussion - Thread 2
Post by: KSHavre on 11/21/2019 09:57 pm
Starlink (and other constellations) will have to fight against 5G and well-established conventional network providers with deep pockets and strong political support. They are not going to go down without a fight.
LEO constellations have an edge when it comes to niche markets like airline and naval broadband and developing countries, but that's not where the Mars colony kind of money is.

As a rural Texas resident with ridiculously expensive choices for home internet, I disagree. There are no conventional network providers at all among my choices. A local telephone coop 5mbs @$90/mo, a rural wireless broadband service offering 3mbs down-1mbs up @$80/mo, and cell phone data (which is sketchy, but what I use now).

There will be plenty of domestic users of Starkink, supporting OCCUPY MARS with every key stroke. If nothing else, it will force the status quo to become competitive price-wise for their urban users. As well as provide new startup providers a source of service to distribute at a lower rate. It has been a long time coming, but SpaceX will level the playing field in this department and I suspect adoption will generate significant income for Starship development.

When I read the inner quote, I said to myself,  "South Texas must be a developing area."  Some of my customers can't even get cell coverage and must depend on satellite service.  It stinks and I, for one, am eagerly waiting until I can buy (and recommend) Starlink service.  Perhaps as early as next year.  I am quite positive there are other rural areas across the USA and other places that just don't have much in the way of options.

Before the mods get a chance to move this discussion to the Starlink thread... Here is the data that helps support the argument that there is a market for affordable Broadband in the US:

https://www.census.gov/library/stories/2018/12/rural-and-lower-income-counties-lag-nation-internet-subscription.html

Title: Re: Starlink : General Discussion - Thread 2
Post by: Mandella on 11/21/2019 10:24 pm
Starlink (and other constellations) will have to fight against 5G and well-established conventional network providers with deep pockets and strong political support. They are not going to go down without a fight.
LEO constellations have an edge when it comes to niche markets like airline and naval broadband and developing countries, but that's not where the Mars colony kind of money is.

As a rural Texas resident with ridiculously expensive choices for home internet, I disagree. There are no conventional network providers at all among my choices. A local telephone coop 5mbs @$90/mo, a rural wireless broadband service offering 3mbs down-1mbs up @$80/mo, and cell phone data (which is sketchy, but what I use now).

There will be plenty of domestic users of Starkink, supporting OCCUPY MARS with every key stroke. If nothing else, it will force the status quo to become competitive price-wise for their urban users. As well as provide new startup providers a source of service to distribute at a lower rate. It has been a long time coming, but SpaceX will level the playing field in this department and I suspect adoption will generate significant income for Starship development.

When I read the inner quote, I said to myself,  "South Texas must be a developing area."  Some of my customers can't even get cell coverage and must depend on satellite service.  It stinks and I, for one, am eagerly waiting until I can buy (and recommend) Starlink service.  Perhaps as early as next year.  I am quite positive there are other rural areas across the USA and other places that just don't have much in the way of options.

/Waves hand.

I know we're being off topic, but I think it can be important to let folks know just how underserved a lot of America is for broadband. Here in west Georgia, not really even that deep in the sticks, my options are satellite and putting up a mast with a Yagi antenna with booster just to get 3G.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Danderman on 11/21/2019 11:37 pm
Now that SpaceX has discovered that the United States can be fully covered by Starlink before equatorial regions, they plan to focus on covering the US as soon as possible.

My question is what happens when they subsequently cover the equatorial regions, won't that mean superfluous coverage of the United States?
Title: Re: Starlink : General Discussion - Thread 2
Post by: mark_m on 11/21/2019 11:48 pm
Now that SpaceX has discovered that the United States can be fully covered by Starlink before equatorial regions, they plan to focus on covering the US as soon as possible.

My question is what happens when they subsequently cover the equatorial regions, won't that mean superfluous coverage of the United States?

IANARS, but I would imagine it would take fewer satellites to use lower inclination orbits fill out full equatorial coverage, which wouldn't add to the general CONUS coverage. (Although it seems reasonable that they wouldn't use any inclinations much lower than one which results from a due-east launch.)

But this is theoretical; isn't the planned configuration known?
Title: Re: Starlink : General Discussion - Thread 2
Post by: Danderman on 11/21/2019 11:53 pm
Since SpaceX doesn't have any launch sites near the Equator, and their current sites are in the US, I am not sure if they have any good options
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 11/21/2019 11:59 pm
More sats over the U.S. and other highly populated parts of the world means more bandwidth available.  Their initial plan was to completely overlay the initial shell with another one at nearly identical inclination to get more bandwidth.
Title: Re: Starlink : General Discussion - Thread 2
Post by: AC in NC on 11/21/2019 11:59 pm
[1]Now that SpaceX has discovered that the United States can be fully covered by Starlink before equatorial regions,
[2]they plan to focus on covering the US as soon as possible.
[3]My question is what happens when they subsequently cover the equatorial regions,
[4]won't that mean superfluous coverage of the United States?

1 - The premise of this framing is not in evidence.
3 - As I read the filings, there is nothing that amounts to "subsequent coverage"
4 - No.  The capacity for the high-density market latitudes will satisfy equatorial regions for the foreseeable future.

Since SpaceX doesn't have any launch sites near the Equator, and their current sites are in the US, I am not sure if they have any good options

I don't think they need any.  Not seeing any inclinations below 30 degrees.  I could be missing something.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Asteroza on 11/22/2019 12:42 am

These things matter. There are hard costs and limited funds. People shouldn't forget that.

Regarding financing for Starship, one word...

                                                                                   Starlink

If that progresses as planned, SpaceX will not have issues with financing going forward and optics will be less of an issue.
Starlink (and other constellations) will have to fight against 5G and well-established conventional network providers with deep pockets and strong political support. They are not going to go down without a fight.
LEO constellations have an edge when it comes to niche markets like airline and naval broadband and developing countries, but that's not where the Mars colony kind of money is.

Uh, I hate to break the bad news, but 5G rollouts are going to be long and painful, and run the risk of bankrupting companies. The density of cells necessary to achieve high speeds is no laughing matter, the costs of acquiring new tower space is going to be insane. Anybody who bought up the old PCS cellular stations (which were also high density) has a head start. Most carriers don't have the capital tables to actually support a full rollout.

Now, conventional fiber optic broadband penetration and associated wifi may change the situation for terrestrial telecomms. There has been serious talk again about federated wifi access, but the sticking point is payment schemes. There's been some blockchain noises to handle the payment schemes, but I can't speak on their merits. Past examples being Fon, and currently Express WiFi by Facebook. ISP's are also bundling wifi with their leased modem routers, such that they can piggyback their own federated wifi on customer equipment (and get them to effectively cover the cost).

But that does nothing for people in deep suburban/exurb areas, especially on the go. Starlink won't do anything for mobile uses (maybe parked RV's being the exception), but as a backhaul alternative in rural cell sites to avoid the fiber optic outlay is an interesting tactic though. Also covers mobile cell sites used for high density events and emergency response.
Title: Re: Starlink : General Discussion - Thread 2
Post by: Danderman on 11/22/2019 12:51 am
[1]Now that SpaceX has discovered that the United States can be fully covered by Starlink before equatorial regions,
[2]they plan to focus on covering the US as soon as possible.
[3]My question is what happens when they subsequently cover the equatorial regions,
[4]won't that mean superfluous coverage of the United States?

1 - The premise of this framing is not in evidence.
3 - As I read the filings, there is nothing that amounts to "subsequent coverage"
4 - No.  The capacity for the high-density market latitudes will satisfy equatorial regions for the foreseeable future.

Since SpaceX doesn't have any launch sites near the Equator, and their current sites are in the US, I am not sure if they have any good options

I don't think they need any.  Not seeing any inclinations below 30 degrees.  I could be missing something.

Assuming an architecture where the US is continuously covered with equally spaced satellites, both within each plane, and between planes, the equatorial regions will not have continuous coverage.

In order to provide equatorial regions similar continuous coverage, satellites would have to be evenly spaced within planes and between planes. Such coverage would result in extra satellites at higher latitudes.

What I gather from earlier posts is that SpaceX considers this a feature not a bug, since the “extra” satellites could provide additional bandwidth. I am guessing that these extra satellites would operate at a different frequency, or better put, SpaceX would use multiple frequencies to avoid confusing the user terminals.
Title: Re: Starlink : General Discussion - Thread 2
Post by: AC in NC on 11/22/2019 01:03 am
Assuming an architecture where the US is continuously covered with equally spaced satellites, both within each plane, and between planes, the equatorial regions will not have continuous coverage.

I don't think this is true.  Why do you think this?
Title: Re: Starlink : General Discussion - Thread 2
Post by: Danderman on 11/22/2019 01:29 am
Assuming an architecture where the US is continuously covered with equally spaced satellites, both within each plane, and between planes, the equatorial regions will not have continuous coverage.

I don't think this is true.  Why do you think this?

Maybe because if there were any gaps between the ground tracks of the satellites, service would be interrupted.
Title: Re: Starlink : General Discussion - Thread 2
Post by: AC in NC on 11/22/2019 01:36 am
Assuming an architecture where the US is continuously covered with equally spaced satellites, both within each plane, and between planes, the equatorial regions will not have continuous coverage.
I don't think this is true.  Why do you think this?
Maybe because if there were any gaps between the ground tracks of the satellites, service would be interrupted.

A continuously covered US does not necessarily mean there will be ground track gaps at the equators.  I think you are leaving an integral premise of your concerns unstated.
Title: Re: Starlink : General Discussion - Thread 2
Post by: lamid on 11/22/2019 09:03 am
Starlink SpaceX 20 planes with 20 satellites continuous coverage between 28-60 ° latitude,
altitude 550 km, inclination 53°.
https://youtu.be/fPbCtF9iUdg
coverage gaps:
Title: Re: Starlink : General Discussion - Thread 2
Post by: sferrin on 11/22/2019 09:38 am

These things matter. There are hard costs and limited funds. People shouldn't forget that.

Regarding financing for Starship, one word...

                                                                                   Starlink

If that progresses as planned, SpaceX will not have issues with financing going forward and optics will be less of an issue.
Starlink (and other constellations) will have to fight against 5G and well-established conventional network providers with deep pockets and strong political support. They are not going to go down without a fight.
LEO constellations have an edge when it comes to niche markets like airline and naval broadband and developing countries, but that's not where the Mars colony kind of money is.

5G has a giant black eye (in the US anyway) due to the China/Huawei fiasco.

Exactly the opposite. U.S. carriers aren't using Huawei 5G.

https://www.washingtonpost.com/technology/2019/04/10/us-spat-with-huawei-explained/

"As U.S. officials have pressured allies not to use networking gear from Chinese technology giant Huawei over spying concerns, President Trump has urged American companies to “step up” and compete to provide the next generation of high-speed, low-lag wireless service known as 5G.

There’s just one problem: Barely any U.S. companies manufacture the technology’s most critical components.

The absence of a major U.S. alternative to foreign suppliers of 5G networking equipment underscores the growing dominance of Huawei, which has evolved into the world’s biggest supplier of telecom equipment, sparking fears within the Trump administration that a 5G network powered by Huawei’s wireless parts could endanger national security. And it throws into sharp relief the years-long retreat by U.S. firms from that market."


Title: Re: Starlink : General Discussion - Thread 2
Post by: AC in NC on 11/22/2019 02:44 pm
Coverage gaps re:  Starlink SpaceX 20 planes with 20 satellites continuous coverage between 28-60 ° latitude,
altitude 550 km, inclination 53°.

Yes.

A constellation continuously covering CONUS can have equatorial coverage gaps.
A constellation continuously covering CONUS does not necessarily have equatorial coverage gaps.

The difference relates to Danderman's unstated premise.
Title: Re: Starlink : General Discussion - Thread 2
Post by: RedLineTrain on 11/22/2019 04:45 pm
I don't doubt that there's a viable market for this service, assuming a reasonable price, but I wonder about how fast the service can be rolled out.  Other constellations have been more slow-and-steady on adoption.  Iridium is just now hitting its stride, 20 years later.
Title: Re: Starlink : General Discussion - Thread 2
Post by: happyflower on 11/22/2019 05:45 pm
I don't doubt that there's a viable market for this service, assuming a reasonable price, but I wonder about how fast the service can be rolled out.  Other constellations have been more slow-and-steady on adoption.  Iridium is just now hitting its stride, 20 years later.

The obvious advantage for Starlink is near free launch services. I don't see Iridium getting this "feature".
Title: Re: Starlink : General Discussion - Thread 2
Post by: RedLineTrain on 11/22/2019 05:51 pm
I don't doubt that there's a viable market for this service, assuming a reasonable price, but I wonder about how fast the service can be rolled out.  Other constellations have been more slow-and-steady on adoption.  Iridium is just now hitting its stride, 20 years later.

The obvious advantage for Starlink is near free launch services. I don't see Iridium getting this "feature".

My point is that even if Starlink could somehow teleport 42,000 satellites into orbit, the roll out and adoption rate for the service may be slower than we hope.
Title: Re: Starlink : General Discussion - Thread 2
Post by: SteveU on 11/22/2019 06:07 pm
I don't doubt that there's a viable market for this service, assuming a reasonable price, but I wonder about how fast the service can be rolled out.  Other constellations have been more slow-and-steady on adoption.  Iridium is just now hitting its stride, 20 years later.

The obvious advantage for Starlink is near free launch services. I don't see Iridium getting this "feature".

My point is that even if Starlink could somehow teleport 42,000 satellites into orbit, the roll out and adoption rate for the service may be slower than we hope.
Speed of adoption really depends on the price point .  IMO Iridium took years because people didn't see the value initially.
Title: Re: Starlink : General Discussion - Thread 2
Post by: AC in NC on 11/22/2019 06:43 pm
I don't doubt that there's a viable market for this service, assuming a reasonable price, but I wonder about how fast the service can be rolled out.  Other constellations have been more slow-and-steady on adoption.  Iridium is just now hitting its stride, 20 years later.

The obvious advantage for Starlink is near free launch services. I don't see Iridium getting this "feature".

My point is that even if Starlink could somehow teleport 42,000 satellites into orbit, the roll out and adoption rate for the service may be slower than we hope.

It may simply be a casual thought, but if we were to look at your two questions for discussion purposes, you sort of get the following:

Starlink Retail Adoption Cadence as a Curiousity (eg: "I wonder about"):

This initial framing is undertandable but essentially an unknown.  As such, it's sort of not worth worrying.  It can be interesting to spitball but there are so many factors that are, to us, unquantifiable it doesn't much interest me though I wouldn't begrudge anyone's interest.

Starlink Retail Adoption Cadence as a Concern (eg: "May be slower than we hope"):

This latter framing is tautologically true.  The cost of "hope" is nil and therefore the demand for sooner approaches infinity.   ;D

But there are very practical benchmarks for what cadence is necessary and desireable, amongst which are:

1) Constellation Deployment to meet regulatory deadlines
2) Constellation Deployment sufficient for Acceptable Competitive Positioning
3) Retail Adoption Sufficient for Acceptable Cash Flows

To these:

1) I suspect Falcon 9 is is sufficient to satisfy this benchmark and so I'm not much worried about it.  Starlink makes it easier but not necessary

2) I suspect the SX advantages on Launch Cost and consequently Constellation size is such that, coupled with impediments to competitors ability to move faster, SX is fine here and even if surpassed early could overtake and run away with the market.

3) I suspect the move to stainless has reduced costs such that long-term funding isn't a huge concern, but obviously more $$$ faster is always helpful.  So then here, what might we expect from an early roll-out.

Early Rollout:

The 53 degree inclination puts the intial ground track north of the US Border AIUI but sufficient to service the northern tier of the United States with significant rural expanses.  The remark of someone elsewhere on Texas service makes me think there is an underserved market.

After Beta-Testing some users and IF they can get a reliable service, then I'd imagine multiples of 100K customers would be readily achievable at a revenue of arguably $100M per 100K customers per year.  And that's just for the US Market based on easier regulatory hurdles.  I'd discount early penetration into other developed markets.

However, I suspect there would also be a worldwide demand of significant opportunity to sell into underdeveloped regions where they were (perhaps) less concerned about erecting regulatory hurdles.  For much of the world, the axiom might well be "Any (ethernet)port in a storm".  I'm not even sure coverage gaps would make service unsellable although here you are talking about areas that are desparate for any connectivity.

And even a modest coverage with gaps could be marketable for certain commericial purposes over the oceans.

Lot of blathering there about a bunch of unknowables, but my thoughts based on your casual musings.
 
Title: Re: Starlink : General Discussion - Thread 2
Post by: AC in NC on 11/22/2019 06:55 pm
On the point "Falcon 9 Sufficient for Starlink" it's probably been done before but in big round numbers to meet regulatory deadlines, you need:

6K constellation by EOY 2024 and a 12K constellation by EOY 2027.

6K constellation is roughly 100 launches and can be done (roughly) with a run-rate equal to next year's 24/yr discounting increased rate.  That increased rate will be necessary to meet EOY 2027
Title: Re: Starlink : General Discussion - Thread 2
Post by: Danderman on 11/22/2019 10:56 pm
Coverage gaps re:  Starlink SpaceX 20 planes with 20 satellites continuous coverage between 28-60 ° latitude,
altitude 550 km, inclination 53°.

Yes.

A constellation continuously covering CONUS can have equatorial coverage gaps.
A constellation continuously covering CONUS does not necessarily have equatorial coverage gaps.

The difference relates to Danderman's unstated premise.

Let me add a third:

Starlink as defined by SpaceX does have equatorial coverage gaps at the end of the initial phase.
Title: Re: Starlink : General Discussion - Thread 2
Post by: AC in NC on 11/22/2019 11:28 pm
Starlink as defined by SpaceX does have equatorial coverage gaps at the end of the initial phase.

The 4409 Sat Constellation?  I'd be stunned if that were the case.  10x the population lamid posted above?

The point remains:  The 30 degree and up constellation will cover the equator.
Title: Re: Starlink : General Discussion - Thread 2
Post by: gongora on 11/22/2019 11:35 pm
Coverage gaps re:  Starlink SpaceX 20 planes with 20 satellites continuous coverage between 28-60 ° latitude,
altitude 550 km, inclination 53°.

Yes.

A constellation continuously covering CONUS can have equatorial coverage gaps.
A constellation continuously covering CONUS does not necessarily have equatorial coverage gaps.

The difference relates to Danderman's unstated premise.

Let me add a third:

Starlink as defined by SpaceX does have equatorial coverage gaps at the end of the initial phase.

The initial shell (1500 sats) covers the equator.  SpaceX will begin offering service at higher latitudes before they have full equatorial coverage.
Title: Re: Starlink : General Discussion - Thread 2
Post by: lamid on 11/23/2019 02:32 am
Yes, 1584 satellites in altitude 550 km  covers latitude -60°-60°.
Older version 24 planes with 66 satellites
(https://upload.wikimedia.org/wikipedia/commons/4/49/Starlink_24planes_a_66sat_sum_1584_satelites.png)
New 72 planes with 22
(https://upload.wikimedia.org/wikipedia/commons/1/1a/Starlink_SpaceX_1584_satellites_72_Planes_22each.png)
Title: Re: Starlink : General Discussion - Thread 2
Post by: AC in NC on 11/23/2019 02:48 am