SpaceX F9: Starlink v1 Flight 1 : November 11, 2019 - DISCUSSION

[John Santos]

Someone in the Starlink General discussion thread if the octograbber had grabbed the booster.  Interesting question, but it belongs here, not in the other thread.  Does anyone know?

[SDSmith]

So the network topology they're going for with the current iteration is akin to bent-pipe reflectors taking between users and ground stations? And that's the version that's going to go live for northern US and parts of Canada next year? How many ground stations do they have set up now?

6 Ku-band, 5 Ka-band in the US.
https://forum.nasaspaceflight.com/index.php?topic=48981.msg1990162#msg1990162

Any estimate as to how many will be needed for US coverage?

[gongora]

So the network topology they're going for with the current iteration is akin to bent-pipe reflectors taking between users and ground stations? And that's the version that's going to go live for northern US and parts of Canada next year? How many ground stations do they have set up now?

6 Ku-band, 5 Ka-band in the US.
https://forum.nasaspaceflight.com/index.php?topic=48981.msg1990162#msg1990162

Any estimate as to how many will be needed for US coverage?

They might not need many more gateways for initial service, more gateways would be needed as the amount of traffic grows.  Still need about 10 more launches.

[theonlyspace]

Did the fairings land in the nets aboard the two fairing recovery ships ?

[gongora]

Did the fairings land in the nets aboard the two fairing recovery ships ?

The fairing recovery ships encountered some rough weather on their way out.  They ended up aborting the recovery attempt and returning to shore before the launch.

[DecoLV]

Fairing recovery was cancelled prior to launch; cause unknown but allegedly due to rough seas in same ocean where OSISLY was fine today.

[sevenperforce]

Fairing recovery was cancelled prior to launch; cause unknown but allegedly due to rough seas in same ocean where OSISLY was fine today.

OCISLY was showing a LOT of back and forth during the landing.

[eriblo]

I'm sure releasing the tension bars causes a spring like motion which then propells and spreads the sats away from the stage and eachother. Just a guess but it seems pretty logical, things under tension just tend to spring back once thetension is released.

You may be right, but that's not what SpaceX thought on the previous launch.  They were very deliberate in spinning the second stage and explained that this would provide the necessary differential momentum.  Maybe there are small springs between the satellites that are released at the time the tension bar is released.  Something is different this time.

The second stage was clearly rotating at separation for this launch as well.

Aha!  You are right.  It's not rotating as rapidly as last time, but there is a spin there.  Also not much background to view it against.  Ok, I retract my observation.

The only background I saw was the earth terminator. It very slowly was moving upwards in the shot. Do we know the terminator movement wasn't from the rotation around the earth?

At T+1:00:17 the Moon appears behind the Starlink stack and moves up and out of frame at T+1:00:23. Right before the "fortuitous video dropout at separation" we start seeing the lightened horizon appearing on the bottom right and after the video is back we see a hint of the Sun moving out of the top right of the view at T+1:01:21.

The deployment took place between Australia and Antarctica at ~15:57 UTC, so the Moon should be above the horizon at ~337° (NNW) and the Sun below the horizon at ~167° (SSE).  So if I have the geometry right the stage is rotating mostly perpendicular to the surface (Earth is to the left in the view) at about 0.5 rpm.

EDIT: Got flipped around, Earth might be to the right (blaming Australia) - fisheye lenses means that the apparent phase of the Moon and the curvature of the horizon do not necessarily agree but the first mission had a CCW spin seen from above.

[punder]

Okay do y'all really think SpaceX is trying to hide something about the deployment? It seems unlikely but what do I know.

I mean, no one else is doing anything remotely close to this. Why would they need to hide anything?

[gongora]

Okay do y'all really think SpaceX is trying to hide something about the deployment? It seems unlikely but what do I know.

I mean, no one else is doing anything remotely close to this. Why would they need to hide anything?

Intentionally releasing debris during satellite deployment is discouraged, and SpaceX appears to be doing that.

[eriblo]

Okay do y'all really think SpaceX is trying to hide something about the deployment? It seems unlikely but what do I know.

I mean, no one else is doing anything remotely close to this. Why would they need to hide anything?

Intentionally releasing debris during satellite deployment is discouraged, and SpaceX appears to be doing that.

Yes, they might want to avoid bad PR but on the other hand most of those who care would know regardless and then they just look shady... The first launch was of course much worse, these ones will reenter much sooner (and will not cross ISS altitude).

The drop out might easily be due to loss of directional downlink during the horizontal rotation (easily predicted ahead of time). They could on the other hand have released a full video later (assuming that it is cached and downlinked for engineering purposes before reentry), so some might hesitate to put away the tinfoil hats

[rsdavis9]

https://twitter.com/HansKoenigsmann/status/1193944631421132801

So did they maybe use starlink for the drone ship coverage?

[gongora]

https://twitter.com/HansKoenigsmann/status/1193944631421132801

So did they maybe use starlink for the drone ship coverage?

No

[mme]

Fairing recovery was cancelled prior to launch; cause unknown but allegedly due to rough seas in same ocean where OSISLY was fine today.

They encountered rough seas on the way out and were concerned the net support structure was damaged. It's a big ocean, a multi-day journey and OSISLY and Ms * are completely different beasts. Why the implication they are lying?

[hplan]

The pregame show mentioned something about quadrupling the data bandwidth of these new starlings -- in passing, as though it were a minor point.

12,000 satellites at 20 gbps over USA 5% of the time for 300 million people gives 13 gigabytes of data per month for each person in the USA.

42,000 satellites at 80 gbps gives 182 gigabytes of data per month per person -- enough to meet the entire consumer broadband network bandwidth needs of the country, if my math is right.


 

[spacenut]

Still no answer about the Octograbber securing the booster?

[gongora]

The pregame show mentioned something about quadrupling the data bandwidth of these new starlings -- in passing, as though it were a minor point.

The previous set of satellites didn't have the Ka-band equipment.  Most of the increase on this set would just be from using Ka-band as well as Ku-band.

[stcks]

Still no answer about the Octograbber securing the booster?

Unless you know someone on the recovery ships, don't expect an answer until it arrives back at port and someone snaps a picture.

[theonlyspace]

Hopefully they do not return with a empty ship the booster having fallen overboard due to rough seas

[AndrewRG10]

Hopefully they do not return with a empty ship the booster having fallen overboard due to rough seas

That's only ever happened once in history and it was because the Octagrabber couldn't fit on the booster.
1. The Octagrabber will immediately go out and grab the booster
2. There were several landings throughout 2016 and 2017 which didn't have an Octagrabber but the booster never fell over in those landings. Heck even Iridium-7 with one of the harshest seas on landing, had no Octagrabber but returned fine and that booster flew again for the fourth time today.