Deep Space Industries vs Planetary Resources

[Hyperion5]

http://www.guardian.co.uk/science/2013/jan/22/space-mining-gold-asteroids

http://www.slashgear.com/planetary-resources-shows-off-full-scale-arkyd-100-space-telescope-prototype-22266215/

Announced only within the last week, a new firm called "Deep Space Industries" has jumped into the asteroid mining business with the Google billionaires' Planetary Resources.  Already we're seeing two different business models, with DSI concentrating on only in-space extraction and refueling of satellites, while PR is considering bringing back rare earth metals to Earth.  But rather than me summarize things too much, I'll leave it up to you, the members of this forum, to get into the details on both companies' plans. 

There's a lot to think about in this new area of competition.  Can asteroid mining become a profitable venture?  Which company has the better business plan?  Will either of these companies succeed?  How big of an industry could this become?  What kinds of things do both firms need to make this more profitable? 

You get the idea.  Does anyone have a guess as to how long it'll take before either firm sees a profit, if ever? 

[Robotbeat]

When/if either venture ever first makes a profit, it will not be directly from mining asteroids.

[oldAtlas_Eguy]

The launch costs for launching a secondary into a GTO is ~$15,000/kg. So three 25 kg cubesats launch costs comes to ~$1.2M on a SpaceX F9. But there is also sat prep costs which could be as much as an additional $1M if there is significant fueling and integration. Making the launch costs as much as $2.2M. Satellite construction requires buying some very expensive parts like HAL thrusters, would probably involve an additional several $2-3M. The rest of the parts are very cheap for cubesats which are in the $10-100K ranges, such as the rad-hard computers available for cubesats. Deep space communications to/from these cubesats will be a problem and could end being the most expensive item in the cubesats operation, post 2015 (if successfully deployed operations would be over 2015-2017).

DSI, if they have 20 people for 3 years that build and operate their 3 cubesats then would be a cost of ~$12M. So total expenditures for 3 years including sat construction and launch costs for DSI could be $17-20M. That is in-line with their statement about funding needing to raise $20M in funding. If they can build and launch their 3 cubesats for <$5M + $12M for their manpower over 3 years, then a data contract with NASA of >$20M for delivery of data on an asteroid if one sat successfully gathers data of an asteroid, DSI could make a profit on the first mission.

[Hyperion5]

The launch costs for launching a secondary into a GTO is ~$15,000/kg. So three 25 kg cubesats launch costs comes to ~$1.2M on a SpaceX F9. But there is also sat prep costs which could be as much as an additional $1M if there is significant fueling and integration. Making the launch costs as much as $2.2M. Satellite construction requires buying some very expensive parts like HAL thrusters, would probably involve an additional several $2-3M. The rest of the parts are very cheap for cubesats which are in the $10-100K ranges, such as the rad-hard computers available for cubesats. Deep space communications to/from these cubesats will be a problem and could end being the most expensive item in the cubesats operation, post 2015 (if successfully deployed operations would be over 2015-2017).

DSI, if they have 20 people for 3 years that build and operate their 3 cubesats then would be a cost of ~$12M. So total expenditures for 3 years including sat construction and launch costs for DSI could be $17-20M. That is in-line with their statement about funding needing to raise $20M in funding. If they can build and launch their 3 cubesats for <$5M + $12M for their manpower over 3 years, then a data contract with NASA of >$20M for delivery of data on an asteroid if one sat successfully gathers data of an asteroid, DSI could make a profit on the first mission.

I'd been wondering how the economics of that would work.  Thanks!  Any opinion as to which firm has the better business model?  DSI I've read is only going to do things in space (refueling satellites, building space stations, refining ores, etc) while PR is saying they might bring things like platinum back to the earth if it's valuable enough.  What kind of prices would we need to see for platinum or rare earth metals for it to be worth bringing it back to the earth's surface? 

If it's more than market prices, is there any chance it'd be worth it to a country like Japan, which has had its access to rare earth metals denied by China due to political spats?

[oldAtlas_Eguy]

PR's Arkayd 100 series sats will be more expensive per sat but also will probably have a higher success rate of delivering data. Also there are multiple customers for that data other than NASA.

Remember both companies will get $0 if thier sats don't deliver good data (a NASA SAA or a commercial contract payable on delivery). That is what they are both risking during the first round of sat building and launch. From that standpoint both business models are very similar during the first 5 years. DSI will just be spending less than PR.

BTW a NASA SAA contract with either would have virtually $0 outlay from the government until ~FY2017 or later.

[Borklund]

Thanks a bunch for your insight oldAtlas_Eguy!

[jabe]

I just hope they release some good educational out reach materials.  I find they underestimate their "audience's" intelligence and want some more specifics.  i.e. engine type, power usage, orbital parameters..
jb

[oldAtlas_Eguy]

I just hope they release some good educational out reach materials.  I find they underestimate their "audience's" intelligence and want some more specifics.  i.e. engine type, power usage, orbital parameters..
jb

Sensors?

[go4mars]

What kind of prices would we need to see for platinum or rare earth metals for it to be worth bringing it back to the earth's surface? 

This was discussed quite a bit on one of the PR threads, but basically it comes down to assumptions which have error bars bigger than a blue whales tail.

[RanulfC]

What kind of prices would we need to see for platinum or rare earth metals for it to be worth bringing it back to the earth's surface? 

This was discussed quite a bit on one of the PR threads, but basically it comes down to assumptions which have error bars bigger than a blue whales tail.

So a more viable plane should aim for sizing of a smaller whale? How would using a Whale Sharks tail fare? Is vertical rather than horizontal orientation a factor? 

Randy

[mlindner]

DSI, if they have 20 people for 3 years that build and operate their 3 cubesats then would be a cost of ~$12M.

You only need 2-3 people to operate a cubesat mission, their complexity is quite low.

[RocketmanUS]

Pr
1st start off with LEO telescopes public can buy time on.
2nd send probes to NEA with possible sale of data to NASA.

DSI
1st start off with probes to NEA that NASA could buy data on.
2nd send probes for return samples.

Both will need to develop a way to mine and deliver commodities to the customers. They will not know what commodities they will have to sell till they know what is available at the NEA's and what the future customer's needs are.

Propellants delivered to EML1/2, LLO, and Mars orbit are near term options. Long term with new technology would be in space alloys and plastics made into simple structures ( boom, tanks, ect. )

Both will have to deal with disposal of the waste by product from mining the NEA's.

Time till profit.
Both could see a profit in a few years if they can sell their first commodity ( data and images still and video ).

The big profit will be from who can build off world.

Earth does not need to import from NEA's, we already have it here. So it will be for space use.

Both will need cheaper launch systems that launch when they need them too ( not wait year(s) after first promise date ). And they will both and others need a LEO assemble/depot station(s) to work from. For crew/cargo to depart from LEO and a place to store items till they are sent to there destination.

[sanman]

But gentlemen, don't you think that if/when things ramp up, then the costs could plunge very quickly? It seems that all this space hardware is so expensive because hardly anybody's gotten the chance to space-rate their equipment. Once enough stuff starts flying, and there's much more data available, then probably there would be room for cheaper entrants to disrupt the cost chain.

In what order do you all expect cost disruptions to happen? Which places along the chain will get disrupted first?

Btw, here is the latest update from Planetary Resources:



Some very strong and direct questions from the lady, and good answers given back:

[happyflower]

Earth does not need to import from NEA's, we already have it here. So it will be for space use.

This has not been proven yet.

The reason why Platinum group metals are used in small quantities, is because they exists in small quantities. These metals have amazing qualities that can really be used more often and in many industries than the current situation. Therefore if the materials "can" be brought down to Earth with some reasonable price, the use of these metals will explode. Again I am not saying this is for sure, but dismissing it out of hand that Earth will not need material from Space is short sighted.

[RocketmanUS]

Earth does not need to import from NEA's, we already have it here. So it will be for space use.

This has not been proven yet.

The reason why Platinum group metals are used in small quantities, is because they exists in small quantities. These metals have amazing qualities that can really be used more often and in many industries than the current situation. Therefore if the materials "can" be brought down to Earth with some reasonable price, the use of these metals will explode. Again I am not saying this is for sure, but dismissing it out of hand that Earth will not need material from Space is short sighted.

We don't mine enough of it right now, that is why the supply is down. The so called environmental laws ( the U.S. has shut down a lot of mining, however imports from other nations ) have slowed things down. Also economical methods of mining the metals and the lack of recycling.

When mining for Platinum group metals or gold there are other item that can be extracted from the raw material to lower cost and improve real  environmental impact.

Keep in mined that a lot of the metal is put in the form of investment/collectable coins.

Asteroid mining business model has to be for in space use. Later if they can get the return cost down then they might send some metals ( other ) back to Earth surface for use. There will be some people willing to pay a premium to have jewelry made from Platinum from space.

[Blackstar]

then a data contract with NASA of >$20M for delivery of data on an asteroid if one sat successfully gathers data of an asteroid, DSI could make a profit on the first mission.

What is this "data" of which you speak?

[go4mars]

Asteroid mining business model has to be for in space use. Later if they can get the return cost down then they might send some metals ( other ) back to Earth surface for use. There will be some people willing to pay a premium to have jewelry made from Platinum from space.

Platinum is very rare on Earth and most of it is produced in one place in Africa.  I agree that a lot of it will be ideally used in space, PR talks about bringing it in industrial-scale quantities (far exceeding novelty jewelry demand), shifting the supply/demand price point lower for the element, regardless of provenance. 
Diamandis wrote a book that provides the philosphical roots of his company; entitled: Abundance.     Even the title is telling.  The book is well-written, thought provoking, and pertinent to PR's longer-range goals. 

[JohnFornaro]

OK.  I had another look at Mr. Lewicki's cube sat, with an eye towards not confusing it with DSI's cube sat.

It is, to my eye, 30cm x 30cm x 60cm. (12" x 12" x 24") It weighs 11kg. (24 lbs)

So this device is 18U, right? and weighs as little as it does?

I am having a hard time believing in the utility of this small thing to orbit in LEO and reliably spot and characterize asteroids.

then a data contract with NASA of >$20M for delivery of data on an asteroid if one sat successfully gathers data of an asteroid, DSI could make a profit on the first mission.

What is this "data" of which you speak?

My take on his remark has to do with a recent BAA by NASA offering $20M for "data".  My understanding of that BAA was that, if you were to successfully land a probe on, say, the Moon, and take pix, then NASA would give you $20M for a full data dump of every last bit of telemetry that you gathered, starting, I suppose, with the launch, and ending with the landing.

[Robotbeat]

OK.  I had another look at Mr. Lewicki's cube sat, with an eye towards not confusing it with DSI's cube sat.

It is, to my eye, 30cm x 30cm x 60cm. (12" x 12" x 24") It weighs 11kg. (24 lbs)

So this device is 18U, right? and weighs as little as it does?

I am having a hard time believing in the utility of this small thing to orbit in LEO and reliably spot and characterize asteroids....

If the optics and sensor can fit, I see no reason why not. Everything else isn't too different from other nanosats or microsats, so should be fine.

You're equating mass and/or size with capability without understanding what drives the requirements for size.

[RocketmanUS]

Asteroid mining business model has to be for in space use. Later if they can get the return cost down then they might send some metals ( other ) back to Earth surface for use. There will be some people willing to pay a premium to have jewelry made from Platinum from space.

Platinum is very rare on Earth and most of it is produced in one place in Africa.  I agree that a lot of it will be ideally used in space, PR talks about bringing it in industrial-scale quantities (far exceeding novelty jewelry demand), shifting the supply/demand price point lower for the element, regardless of provenance. 
Diamandis wrote a book that provides the philosphical roots of his company; entitled: Abundance.     Even the title is telling.  The book is well-written, thought provoking, and pertinent to PR's longer-range goals. 

How much more per year do we need? Double? Triple?
We can increase production. If the supply is increased without demand then the price will fall and the production with it. Just like what happens with gold. And the production is controlled politically, look at diamond mining.

http://en.wikipedia.org/wiki/Platinum
Jewelry is about 31%.

It is rare, however it is a byproduct of other mining. Once someone delivers a means to detect the metal from other material in an economic way then production could increase.

[go4mars]

And the production is controlled politically, look at diamond mining.

Total agreement about diamond mining (marketing control specifically).  I admit I don't know a lot about the dark politics of platinum mining and distribution to offer informed comment, but admit to its possible existence. 

That said, I'd like to see a company dump it on the market for so cheap that mining it on Earth doesn't make sense.  If some clever individual or group can figure out how to increase the supply by 50 times, the price perhaps drop to $50/ounce.  In addition to all of the newfound industrial uses at a given price-point, suddenly guys might be thinking about platinum electroplating for their guitar/bumper/fridge/roof tiles, etc.   

My example seems extreme from our current perspective.  But if there is a viable alternative to extensive mining and leaching with cyanide, at even a comparable price point, it's worth a look.  Crashing the price point is not a bad thing if there are better ways to do things.   

I assume the 'mining space competitively phase' will be after the 'easily reusable BFR availability phase'. 

How much more per year do we need? Double? Triple?
If the supply is increased without demand then the price will fall and the production with it.

[RocketmanUS]

And the production is controlled politically, look at diamond mining.

Total agreement about diamond mining (marketing control specifically).  I admit I don't know a lot about the dark politics of platinum mining and distribution to offer informed comment, but admit to its possible existence. 

That said, I'd like to see a company dump it on the market for so cheap that mining it on Earth doesn't make sense.  If some clever individual or group can figure out how to increase the supply by 50 times, the price perhaps drop to $50/ounce.  In addition to all of the newfound industrial uses at a given price-point, suddenly guys might be thinking about platinum electroplating for their guitar/bumper/fridge/roof tiles, etc.   

My example seems extreme from our current perspective.  But if there is a viable alternative to extensive mining and leaching with cyanide, at even a comparable price point, it's worth a look.  Crashing the price point is not a bad thing if there are better ways to do things.   

I assume the 'mining space competitively phase' will be after the 'easily reusable BFR availability phase'. 

How much more per year do we need? Double? Triple?
If the supply is increased without demand then the price will fall and the production with it.

When the price drops for launch and down mass then it can be done.
For down mass it might be possible to use inflatable capsule ( inflatable heat shield ), with one side with a hatch. Capsule shape for passive control on reentry, only need deorbit burn. Would need to be able to bring enough mass down were the metal could be sold for $50 oz.

[Robert Thompson]

I'm not catching how DSI will characterize targets so as to optimize. Will they absorb larger risk to get to suspect targets faster? My inclination is that several cooperating Palantirs of free photons will win the hare and tortoise race over a Picket's charge of expensive nucleons and reaction mass. But, to borrow K-selection and r-selection, there is a place for a swarm to decent quality platinum group targets, and a place for a hole-in-one best available target. Waiting for that info on how DSI will choose.

[RocketmanUS]

I'm not catching how DSI will characterize targets so as to optimize. Will they absorb larger risk to get to suspect targets faster? My inclination is that several cooperating Palantirs of free photons will win the hare and tortoise race over a Picket's charge of expensive nucleons and reaction mass. But, to borrow K-selection and r-selection, there is a place for a swarm to decent quality platinum group targets, and a place for a hole-in-one best available target. Waiting for that info on how DSI will choose.

For mining the first asteroid should be for propellants.
Later for in space building materials.
Long term of valuable metals.
By the time they are able ( cost effective ) return metal to Earth surface they both would have had the metal already stored in space from earlier mining as a by product.

Keep in mind the profit is not always in "$".

[Robert Thompson]

Uh-uh. I don't sense we're in a r-selection regime in space, yet. So, even for a first target with propellant-yield, the selection process (I think) has to be painstaking and exhaustive. I am wondering where they will get the info to support a painstaking and exhaustive optimization to most recoverably risk scarce investor dollars. A NASA database with orbital elements? That's it? I'm missing a verb.

[RocketmanUS]

Uh-uh. I don't sense we're in a r-selection regime in space, yet. So, even for a first target with propellant-yield, the selection process (I think) has to be painstaking and exhaustive. I am wondering where they will get the info to support a painstaking and exhaustive optimization to most recoverably risk scarce investor dollars. A NASA database with orbital elements? That's it? I'm missing a verb.

Send out 8 probes each on a different launch to reduce risk of loss. Each probe launch should be months apart to see if any changes need to be made on probes launched later.

Choose the best NEA from those that are scanned by the probes. Each probe could be able to scan more than one NEA. A NEA will need to have enough of the needed types of propellants to be mined for profit and a customer for the propellants. Their own miner could even refuel to be moved to another NEA from the mined propellants. They would need miners and tanker craft.

I think for metals they will separate the ores and transport then to a customer were they will process the ore.

I think they are others already working on how to use such space mined materials and process them. They would by the raw material from these two companies.

[JohnFornaro]

You're equating mass and/or size with capability without understanding what drives the requirements for size.

No. 

I'm not seeing any propellant in it, and once the LV sends it from Earth to point A, I don't see it really ever getting to a possible point B.

That's the "capability" I keep harping on.

Hayabusa[/url weighed 510kg wet, and 380kg dry.  That mission lasted for seven years.  True, it brought back a sample.

The cubesats from DSI and PRI are rather tiny, even if they're not scheduled to make a round trip.

I'm not believing what I hear yet.

[Robotbeat]

You're equating mass and/or size with capability without understanding what drives the requirements for size.

No. 

I'm not seeing any propellant in it, and once the LV sends it from Earth to point A, I don't see it really ever getting to a possible point B.

That's the "capability" I keep harping on.

Hayabusa weighed 510kg wet, and 380kg dry.  That mission lasted for seven years.  True, it brought back a sample.

The cubesats from DSI and PRI are rather tiny, even if they're not scheduled to make a round trip.

I'm not believing what I hear yet.

They would use cubesat components and design philosophy.

[QuantumG]

The first of anything technological is rarely a good benchmark for subsequent iterations. Typically, you either do it "better" or you don't do it at all. But hey, they could just be wildly optimistic.. we'll have to wait and see.

[Robotbeat]

The miniaturization possible with cubesat tech (through advances in the last two decades in electronics and MEMS fabrication) is a genuine advancement.  It could possibly allow PR or some such to do a deep space mission for quite cheap. Many, many cubesats have been launched to LEO, but none to deep space, though there are plans. just because larger spacecraft are usually used doesn't mean it is impossible to do it smaller.

[WiresMN]

I would suspect that each sat will have a single or limited multi purpose and be as simple as possible. It would help keep cost and size down.  Single function is a big departure from current deep space sats, but will serve the prospecting purpose well. even more so when trying something new. Fail but fail cheap!

[mlindner]

The miniaturization possible with cubesat tech (through advances in the last two decades in electronics and MEMS fabrication) is a genuine advancement.  It could possibly allow PR or some such to do a deep space mission for quite cheap. Many, many cubesats have been launched to LEO, but none to deep space, though there are plans. just because larger spacecraft are usually used doesn't mean it is impossible to do it smaller.

Yeah, I completely agree. Rather having dealt with cubesats personally, I often have a failure to understand why normal satellites are so _large_. The only things that have to scale with the spacecraft are reaction wheels. Radios are large if you are far from earth. The better an IMU, usually the larger it is for dampening. For a telescope/camera physical size is important for collection area. Besides these issues though I fail to see what makes normal satellites the size of a bus. I can't imagine what you would do with all that volume other than throw in heavy metal structure.

[QuantumG]

Massive transmitters and the power conditioning hardware to power them was always my assumption.

[oldAtlas_Eguy]

Here is the problem:

Data rate (bandwidth) is related to antenna gain and transmitter power. Either you increase the antenna gain or increase the transmitter power to get a higher data rate.

Let's say you can do 10kbits/sec data rate for a 50W transmitter and a certain sized dish antenna. In order to do 1mbits/sec data rate you increase the dish diameter by a factor of 3.16 (and a weight increase of the antenna of a factor of 10) and increase the transmitter power to 500W. The solar array to power a 50W transmitter is let's say 20sqrft (4ft X 5ft), but a solar array to power a 500W transmitter is 200sqrt (8ft X 25ft) as well as weighing 10 times more. So now you have gone from a 20kg sat to one weighing nearly 200kg. Just because you need (or want) a higher data rate.


BTW Voyager went the low (data rate) bandwidth/ low transmiter power route and it is still in communication with Earth even at the edge of the solar system. Although for significant amount of data it takes a great deal of time.

[Robotbeat]

Here is the problem:

Data rate (bandwidth) is related to antenna gain and transmitter power. Either you increase the antenna gain or increase the transmitter power to get a higher data rate.

Let's say you can do 10kbits/sec data rate for a 50W transmitter and a certain sized dish antenna. In order to do 1mbits/sec data rate you increase the dish diameter by a factor of 3.16 (and a weight increase of the antenna of a factor of 10) and increase the transmitter power to 500W. The solar array to power a 50W transmitter is let's say 20sqrft (4ft X 5ft), but a solar array to power a 500W transmitter is 200sqrt (8ft X 25ft) as well as weighing 10 times more. So now you have gone from a 20kg sat to one weighing nearly 200kg. Just because you need (or want) a higher data rate.


BTW Voyager went the low (data rate) bandwidth/ low transmiter power route and it is still in communication with Earth even at the edge of the solar system. Although for significant amount of data it takes a great deal of time.

And this is exactly why Planetary Resources is going for optical communication. It allows a far greater data rate given the same power and transmitter aperture size. This is because of the far shorter wavelength of visible or near-infrared light compared to radiowaves, which means a tiny aperture acts like an ENORMOUS dish antenna.

[Solman]

 Of course if that antenna doubles as a solar concentrator it can simultaneously communicate and provide solar power to a spacecraft traveling to Mars and beyond and be used non simultaneously in other situations. The large size concentrator required at Jupiter and beyond for power also means higher data transmission rate. The concentrator's high specific power and the higher efficiency and much higher specific power of PV using highly concentrated sunlight means dramatically higher power at Mars and beyond vs. non concentrating solar arrays.

[Lar]

And this is exactly why Planetary Resources is going for optical communication. It allows a far greater data rate given the same power and transmitter aperture size. This is because of the far shorter wavelength of visible or near-infrared light compared to radiowaves, which means a tiny aperture acts like an ENORMOUS dish antenna.

I don't quite understand how they are going to point the outbound laser accurately enough. I guess that's the 64K question, isn't it?

I have enough trouble keeping my garage door opener safety beams aligned that I would expect this to be a pretty hard thing to do. Don't you need spacecraft (or at least the transmitting laser) alignment down to thousandths of an arc-second or better??? I didn't actually run the numbers but it seems really small. Are they going to deliberately decollimate it somewhat to decrease the accuracy requirement (at the cost of increased power in transmission or a more sensitive detector or both)?

Are there ways of steering an outbound beam that don't require mechanical devices? would that help in pointing that accurately?

My LEGO models have lash that makes it hard to achieve 2 degrees accuracy, much less thousandths of an arc-second....

[Robotbeat]

Star trackers can be quite small and compact these days, and they may have a clever way to use the scope to get a fine pointing reading at nearing the same time as transmitting data. As far as steering, reaction wheels and magnetic torquers (for desaturating the reaction wheels) are what are normally used in LEO (it's what Hubble uses) and are used for some nanosats as well (some simply use just the mag. torquers or even just a passive magnetic torquer that just keeps the spin rates down), but for deep space magnetic torquers are not feasible (far from Earth's magnetic field) for desaturating the reaction wheels.

So, you can use a cold- or warm-gas thruster system or a pulse plasma system (more Isp, less integration hassle, but just a small amount of propellant) or the emerging higher performing electric propulsion systems.


Off the shelf parts for nanosats (including microsats from 10kg to 100kg), with listed prices:
Magnetic torquer:
http://www.cubesatshop.com/index.php?page=shop.product_details&flypage=flypage.tpl&product_id=102&category_id=7&option=com_virtuemart&Itemid=69

3-axis reaction wheels:
http://www.cubesatshop.com/index.php?page=shop.product_details&flypage=flypage.tpl&product_id=52&category_id=7&option=com_virtuemart&Itemid=69

Cold/warm-gas thrusters:
http://www.cubesatshop.com/index.php?page=shop.product_details&flypage=flypage.tpl&product_id=74&category_id=7&option=com_virtuemart&Itemid=69

Fine Sun-sensor (can get around 0.1 degree pointing precision, enough to get a target in the telescope's field of view):
http://www.cubesatshop.com/index.php?page=shop.product_details&flypage=flypage.tpl&product_id=89&category_id=7&option=com_virtuemart&Itemid=69

Pulse-plasma thruster (~600s Isp, but very, very low total amount of propellant available... though much better ones are available from Busek):
http://www.clyde-space.com/cubesat_shop/propulsion/303_cubesat-pulse-plasma-thruster


Good overview of higher performing propulsion options for cubesat/nanosats, not entirely off-the-shelf and definitely not a listed price, but they have been lab-tested:
http://www.busek.com/cubesatprop__main.htm

[RocketmanUS]

Communication:
1 ) For the laser communication system what is the foot print size of the beam sent from Earth and received at Mars?

Mining:
2 ) Could they bag the NEA, heat it up to extract gasses. Then grind the solid mas up in to powered to separate the powder by heavy and light mass? If in fine powder form it would seem a cheap way to separate different compounds and elements along with magnets and it's color. At least to a point were it could then be refined into what ever they needed.

Reuse and refueling:
With the mind gas they should be able to separate it so they can have some of it to refuel the miner craft and the transporter(s) craft. Miner then moves on to another NEA while the transporter(s) deliver the raw material to the processors or customers.

[mlindner]

Magnetic torquer:
http://www.cubesatshop.com/index.php?page=shop.product_details&flypage=flypage.tpl&product_id=102&category_id=7&option=com_virtuemart&Itemid=69

3-axis reaction wheels:
http://www.cubesatshop.com/index.php?page=shop.product_details&flypage=flypage.tpl&product_id=52&category_id=7&option=com_virtuemart&Itemid=69

Having worked in development of some of the above, the listed prices are very inflated compared to the actual costs of production of those devices. With a student/intern team you can pull the costs down quite a bit. This is the reason we were developing our own in-house rather than buying outside models because we viewed we could produce them of a higher quality and much cheaper than the off the shelf versions. It is very likely that any commercial company will do the same.

The magnetorquer board is a few machined parts, a PCB, some minimal microcontroller and electrical parts, an h-bridge for each torquer and a bunch of space-rated magnetwire (which can be gotten free as the wire for some reason "expires" after a certain amount of time and research groups will just dump it normally).

[Robotbeat]

mlinder: I believe it. But just /having/ a listed price is a pretty big improvement, IMHO, over regular spacecraft parts. The magnetic torquers definitely don't /have/ to cost that much (reaction wheels are a little tougher, though... harder to DIY).

[JohnFornaro]

You're equating mass and/or size with capability without understanding what drives the requirements for size.

No. 

I'm not seeing any propellant in it, and once the LV sends it from Earth to point A, I don't see it really ever getting to a possible point B.

That's the "capability" I keep harping on.

Hayabusa weighed 510kg wet, and 380kg dry.  That mission lasted for seven years.  True, it brought back a sample.

The cubesats from DSI and PRI are rather tiny, even if they're not scheduled to make a round trip.

I'm not believing what I hear yet.

They would use cubesat components and design philosophy.

Well of course, in general.

I'm still not believing in what I hear yet.  The cubesats are too small to have the broad capability that is necessary.

[JohnFornaro]

Having worked in development of some of the above, the listed prices are very inflated compared to the actual costs of production of those devices.

Apparently, SpaceX has found a similar inflation in the list price of a rocket launch.

[JohnFornaro]

Communication:
1 ) For the laser communication system what is the foot print size of the beam sent from Earth and received at Mars?

Mining:
2 ) Could they bag the NEA, heat it up ...

Reuse and refueling:
With the mind gas they should be able to ... deliver the raw material to the processors or customers.

1) How do they get the laser signal out of the Earth's atmosphere, and back thru it?  How do they accomodate the Earth's rotation?  Either that, or, where is the LEO or GEO comm system?  DSN doesn't use lasers, BTW.

2) Not with cubesats.

3) The gas is all in the mind, of course.  At least that part's easy.

[JohnFornaro]

The cubesat shop.

Totally excellent.

[JohnFornaro]

... just because larger spacecraft are usually used doesn't mean it is impossible to do it smaller.

Which is fine, but neither does it mean that it's possible either.

[JohnFornaro]

DSI, if they have 20 people for 3 years that build and operate their 3 cubesats then would be a cost of ~$12M.

You only need 2-3 people to operate a cubesat mission, their complexity is quite low.

That may be, but hea said, "build and operate".  The business plan which has them build a fleet of two sats, and then lay off the builders, is not really the plan of a sustainable company.

[douglas100]

1) How do they get the laser signal out of the Earth's atmosphere, and back thru it?  How do they accomodate the Earth's rotation?  Either that, or, where is the LEO or GEO comm system?  DSN doesn't use lasers, BTW.

The signal would come to what would be essentially an astronomical telescope. So you would not have com in daylight or if it's cloudy. This limits your options. You might have telescopes at several clear weather sites around the world to increase your chances.

As far as the Earth's rotation is concerned, that's almost trivial. The telescope (either altazimuth or polar mounted) would track the spacecraft as it would track any other object on the celestial sphere, turning to counteract the Earth's rotation. The DSN antennas do the same thing.

As you mention, you could get round the difficulties with the Earth's atmosphere by having the receiving telescope in space. Operationally the best place would probably be GSO. That would mean you would only need one ground station. The receiving telescope could point to any part of the celestial sphere that's not too close to the sun and get the laser signal unaffected by the atmosphere. The last part of the signal's journey would be by radio to the ground station.

That option would be expensive, of course, but technically doable.

[Robotbeat]

... just because larger spacecraft are usually used doesn't mean it is impossible to do it smaller.

Which is fine, but neither does it mean that it's possible either.

It IS possible to do recon with a cubesat, end of story. Whether they can do it cheaply and quickly is not a settled question.

You can do Earth observation from a cubesat. You can do it in infrared, you can even do spectroscopy from a cubesat. Simply being able to map out the asteroid would be quite useful, and there's no real good reason you couldn't do it from a cubesat platform (data rate may be an issue).

The big question is figuring out how to do deep space operations with a cubesat. They can already operate and maneuver in LEO, but deep space has higher communication issues.


Planetary believes they can solve the issue by using the telescope to do laser comms. This isn't unreasonable. They can do laser-comms between LEO Arkyds and deep space Arkyds, communicating between LEO and the ground either through gaps in the clouds (data rate would be very high) or simply through radio.

[mlindner]

Communication:
1 ) For the laser communication system what is the foot print size of the beam sent from Earth and received at Mars?

Mining:
2 ) Could they bag the NEA, heat it up ...

Reuse and refueling:
With the mind gas they should be able to ... deliver the raw material to the processors or customers.

1) How do they get the laser signal out of the Earth's atmosphere, and back thru it?  How do they accomodate the Earth's rotation?  Either that, or, where is the LEO or GEO comm system?  DSN doesn't use lasers, BTW.

2) Not with cubesats.

3) The gas is all in the mind, of course.  At least that part's easy.

1) Lasers have constant angular beam diameter set by the dispersion rate of the beam (assuming a vacuum). I would guess that the diameter of the beam from earth to Mars even at closest approach would be greater than the diameter of the entire planet. Hitting the target isn't so much of an issue IMO than getting the dispersion low enough to have high enough power density at the receiving point.

[JohnFornaro]

As far as the Earth's rotation is concerned, that's almost trivial.

You misunderstand me.  I quite realize that telescopes can track objects.  The Earth's rotation will determine the number of probably tracking stations.  Neither of these companies has made any public statements as to how they will pragmatically communicate with their cubesats.

To date, most terrestrial telescopes are passive receivers of information and observations, not transmitters thereof.

That option [GSO or GEO comm station] would be expensive, of course, but technically doable.

Think it thru a mite longer.  All they are stressing is that they can make cheap cubesats from OTS components, and that they have a "secret sauce" that enables more capabilities than hitherto demonstrated for communicating with those sats.

... just because larger spacecraft are usually used doesn't mean it is impossible to do it smaller.

Which is fine, but neither does it mean that it's possible either.

It IS possible to do recon with a cubesat, end of story. Whether they can do it cheaply and quickly is not a settled question.

You can do Earth observation from a cubesat....

Of course it's possible to observe the Earth.  That is not their main objective.

The big question is figuring out how to do deep space operations with a cubesat. They can already operate and maneuver in LEO, but deep space has higher communication issues.

What they've said so far doesn't sound like it's possible to me.  Are you on their board?  You keep banging the drum that what they assert is "technically" possible.

Planetary believes they can solve the issue by using the telescope to do laser comms. This isn't unreasonable. They can do laser-comms between LEO Arkyds and deep space Arkyds, communicating between LEO and the ground either through gaps in the clouds (data rate would be very high) or simply through radio.

Of course they have what you and they assert; not unreasonable assertions.  Now I gotta channel QuantumG:

There is no true Scotsman.

[JohnFornaro]

Communication:
1 ) For the laser communication system what is the foot print size of the beam sent from Earth and received at Mars?

1) How do they get the laser signal out of the Earth's atmosphere, and back thru it?  How do they accomodate the Earth's rotation?  Either that, or, where is the LEO or GEO comm system?  DSN doesn't use lasers, BTW.

1) Lasers have constant angular beam diameter set by the dispersion rate of the beam (assuming a vacuum). I would guess that the diameter of the beam from earth to Mars even at closest approach would be greater than the diameter of the entire planet. Hitting the target isn't so much of an issue IMO than getting the dispersion low enough to have high enough power density at the receiving point.

The relationship between dispersion and power density is exactly the issue I was getting at.  The solar array that is illustrated for the cubesat looks pretty small to be powering and flying the sat, and having enough "oomf" to get a decent signal back to Earth.

Even tho the beam is as wide as the Earth, that angle of dispersion is pretty darn small when you're looking from that sat back to the pinprick of light that is the Earth.  You, or they, will have to aim pretty darn accurately.  Which I assume is "technically" doable, even tho no such demonstration mission has taken place at the present time.

They appear to be asserting that they will solve this communications challenge on the first try.  An investor is supposed to believe that assertion.

[Robotbeat]

Communication:
1 ) For the laser communication system what is the foot print size of the beam sent from Earth and received at Mars?

Mining:
2 ) Could they bag the NEA, heat it up ...

Reuse and refueling:
With the mind gas they should be able to ... deliver the raw material to the processors or customers.

1) How do they get the laser signal out of the Earth's atmosphere, and back thru it?  How do they accomodate the Earth's rotation?  Either that, or, where is the LEO or GEO comm system?  DSN doesn't use lasers, BTW.

2) Not with cubesats.

3) The gas is all in the mind, of course.  At least that part's easy.

1) Lasers have constant angular beam diameter set by the dispersion rate of the beam (assuming a vacuum). I would guess that the diameter of the beam from earth to Mars even at closest approach would be greater than the diameter of the entire planet. Hitting the target isn't so much of an issue IMO than getting the dispersion low enough to have high enough power density at the receiving point.

The beam size is essentially the same size as the smallest discernible feature in a telescope the same aperture. You can see features on Mars from Earth on a telescope smaller than the one Planetary Resources is using, so they should be able to do pretty well.

(Note: this is just because I'm too lazy to do the Rayleigh criterion equation which is basically: half-angle-in-radians-of-beam=1.22*aperturediameter/(wavelengthoflightused) )

[douglas100]

From John Fornaro:

To date, most terrestrial telescopes are passive receivers of information and observations, not transmitters thereof.

(my bold)
Bear in mind that it's the downlink where a high rate is an advantage. The uplink would be mostly command files and the like. It doesn't need an optical transmitter. Ordinary radio should do just fine.

[mlindner]

The relationship between dispersion and power density is exactly the issue I was getting at.  The solar array that is illustrated for the cubesat looks pretty small to be powering and flying the sat, and having enough "oomf" to get a decent signal back to Earth.

Even tho the beam is as wide as the Earth, that angle of dispersion is pretty darn small when you're looking from that sat back to the pinprick of light that is the Earth.  You, or they, will have to aim pretty darn accurately.  Which I assume is "technically" doable, even tho no such demonstration mission has taken place at the present time.

They appear to be asserting that they will solve this communications challenge on the first try.  An investor is supposed to believe that assertion.

Cubesats run quite power negative when transmitting even at very low power with radios so this is no surprise. This is what batteries are for. I haven't seen numbers for laser data transmission, but I would assume it's significantly better.

They already have their investors, so they're currently believing them or at least believing their credentials (which are quite good).

I should note as well no telescope is needed on the ground for data transmission to an LEO satellite. Granted some better equipment and higher flash and modulation rates are needed, but this was done with a tiny off the shelf consumer laser pointer and a standard consumer camera.
See http://www.universetoday.com/93987/amateur-astronomers-flash-the-space-station/
"When the spotlights were off, he said he could still see the [1 Watt] blue laser, which was shone steadily,"

[Robotbeat]

The relationship between dispersion and power density is exactly the issue I was getting at.  The solar array that is illustrated for the cubesat looks pretty small to be powering and flying the sat, and having enough "oomf" to get a decent signal back to Earth.

Even tho the beam is as wide as the Earth, that angle of dispersion is pretty darn small when you're looking from that sat back to the pinprick of light that is the Earth.  You, or they, will have to aim pretty darn accurately.  Which I assume is "technically" doable, even tho no such demonstration mission has taken place at the present time.

They appear to be asserting that they will solve this communications challenge on the first try.  An investor is supposed to believe that assertion.

Cubesats run quite power negative when transmitting even at very low power with radios so this is no surprise. This is what batteries are for. I haven't seen numbers for laser data transmission, but I would assume it's significantly better.

They already have their investors, so they're currently believing them or at least believing their credentials (which are quite good).

I should note as well no telescope is needed on the ground for data transmission to an LEO satellite. Granted some better equipment and higher flash and modulation rates are needed, but this was done with a tiny off the shelf consumer laser pointer and a standard consumer camera.
See http://www.universetoday.com/93987/amateur-astronomers-flash-the-space-station/
"When the spotlights were off, he said he could still see the [1 Watt] blue laser, which was shone steadily,"

This video is great for showing the sort of thing Planetary Resources is thinking about:

[A_M_Swallow]

From John Fornaro:

To date, most terrestrial telescopes are passive receivers of information and observations, not transmitters thereof.

(my bold)
Bear in mind that it's the downlink where a high rate is an advantage. The uplink would be mostly command files and the like. It doesn't need an optical transmitter. Ordinary radio should do just fine.

Using lasers to give orders to the satellite is inadvisable because the sun will frequently be behind the Earth.  Pointing ordinary telescopes at the sun tends to damage light detectors.

[JohnFornaro]

...The solar array that is illustrated for the cubesat looks pretty small to be powering and flying the sat, and having enough "oomf" to get a decent signal back to Earth.

Even tho the beam is as wide as the Earth, ... they will have to aim pretty darn accurately.  Which I assume is "technically" doable, even tho no such demonstration mission has taken place at the present time.

They appear to be asserting that they will solve this communications challenge on the first try.  An investor is supposed to believe that assertion.

Cubesats run quite power negative when transmitting even at very low power with radios so this is no surprise. This is what batteries are for. I haven't seen numbers for laser data transmission, but I would assume it's significantly better.

What comes as no surprise?  That they're going to do it right the first time?  Also, what does "power negative" mean in this context?  The only thing generating electricity up there is the solar panels.

As to laser data transmission rates, I don't know the specifics of their system, since it appears to be proprietary.  I do know that high rates of data transmission across the laboratory do not translate into the same rates of data transmission between the asteroid belt and Earth, particularly when the two are in opposition.  Even so, the video that Chris posted was pretty cool.

They already have their investors, so they're currently believing them or at least believing their credentials (which are quite good).

That's true, they have said that they "already have investors".  They did not say that they don't need any more.  It should be clear, with a bit of reflection, that I was referring to the investors that they'd like to convince.  Right now, I would hold on to my million dollar investment, based on their public statements, and my assessment of their success based on those statements.

I should note as well no telescope is needed on the ground for data transmission to an LEO satellite. ...

Another reminder that I am discussing the communication power cababilities of the cubesat, particularly when it is at opposition.

[Rugoz]

Bringing 1 kilogram from an asteroid back to earth (landing incl.) must already cost more than 50k, right? (50k is the price of 1kg of platinum)

Then you still haven't done any mining, which probably would require tons of equipment for extracting precious metals, unless there are asteroids made of pure platinum floating around in space.

Regarding water mining. Well that certainly sounds easier, however it would require a significant human presence in space in the forseeable future. That could be due to some utterly expensive government program (like the ISS), which would be good for business, however if a massive reduction in launch costs is behind it, bringing in water from asteroids could become less attractive.

[mlindner]

What comes as no surprise?  That they're going to do it right the first time?  Also, what does "power negative" mean in this context?  The only thing generating electricity up there is the solar panels.

In spacecraft mission ops, missions have various "modes" of operation and each has an associated power use rate. This is all labeled out in the power budget during the design phase of the mission (and refined as construction/testing proceeds). Several modes are often "power negative" in the sense that if you leave your spacecraft in that mode over a given orbit (averaged across the orbit eclipse/non-eclipse periods) then you will have a net drain on your battery.

In this sense whenever they are transmitting they will be very power negative. Basically aggregated over all your orbits, this just constrains your maximum average data transmission rate, even though in brief bursts you will have much higher data transmission rates. You are only limited by the short circuit current of your battery (although in reality you want to be significantly below this as it burns out your battery).

This may be the same for full size spacecraft as well, but in well designed cubesats almost all the subsystems are completely powered down when they are not active and they often have several super low power modes beyond that.

As to laser data transmission rates, I don't know the specifics of their system, since it appears to be proprietary.  I do know that high rates of data transmission across the laboratory do not translate into the same rates of data transmission between the asteroid belt and Earth, particularly when the two are in opposition.  Even so, the video that Chris posted was pretty cool.

I agree, lab rates do not correlate to reality. That is what testbed spacecraft are for though, which is what they are working on currently.

The video is from the page I linked in the post above which has a lot more info about how it was done and some of the specifics. So I suggest you take a look at that as well.

[KelvinZero]

Bringing 1 kilogram from an asteroid back to earth (landing incl.) must already cost more than 50k, right? (50k is the price of 1kg of platinum)

Then you still haven't done any mining, which probably would require tons of equipment for extracting precious metals, unless there are asteroids made of pure platinum floating around in space.

Regarding water mining. Well that certainly sounds easier, however it would require a significant human presence in space in the forseeable future. That could be due to some utterly expensive government program (like the ISS), which would be good for business, however if a massive reduction in launch costs is behind it, bringing in water from asteroids could become less attractive.

(Im no expert but..)

I think the first obvious use (of water) would be a propellant depot to refuel the upper stage (Eg a Centaur stage) of an existing launcher after it gets to orbit. This would let us throw much larger unmanned robots at mars with our existing rockets for example.

Cheaper launch from earth would probably bring down the worth of fuel in LEO, but with cheaper launch we would probably have the ability to do something really worthwhile, and that thing would likely benefit from a depot further out than LEO, eg EML2 or even mars orbit. At some point the advantage has to move to using local resources.

[JohnFornaro]

... in well designed cubesats almost all the subsystems are completely powered down when they are not active and they often have several super low power modes beyond that.

Which is fine, and I assumed that the cubesats in question would be "well designed".

Yet another reminder that I am discussing the communication power cababilities of the illustrated cubesat, particularly when it is at opposition.

Do you think that the illustrated "fleet" of two 6U cubesats, shown within some few km of an asteroid, really have the "right stuff" to communicate their observations to the Earth at the range of expected distances, via a laser comm channel to an Earth based telescope?

'Cause I don't think so, and I would have a hard time as an investor, based on the public presentations and that illustration, in parting with substantial capital.  Just sayin'.

[Robotbeat]

Well then you don't understand the enormous difference in wavelength between visible light and radio waves.

[mlindner]

Do you think that the illustrated "fleet" of two 6U cubesats, shown within some few km of an asteroid, really have the "right stuff" to communicate their observations to the Earth at the range of expected distances, via a laser comm channel to an Earth based telescope?

Assuming your beam dispersion is low enough, what makes laser communication nice is that it doesn't fall off with distance nearly as much. The falloff rate is nearly negligible compared to radio. Radio signals fall off with 1/r^2, twice as far, four times as weak. Laser does not follow these rules and an ideal laser will have zero loss no matter the distance.

They've already done laser communication with LRO from earth's surface, news from a few weeks ago. http://www.nasa.gov/mission_pages/LRO/news/mona-lisa.html

[Robotbeat]

Laser still disperses at 1/r^2, but it just starts far more concentrated and the angle is much smaller for the same aperture size.

[joek]

Laser still disperses at 1/r^2, but it just starts far more concentrated and the angle is much smaller for the same aperture size.

Yeah, sort of, more or less, theoretically.  Which tells us nothing as to why laser's might be preferred for such applications, why free-space communications would benefit from what they have to offer, and why they appear to be the prospective choice.  Can you say why, beyond physics/optics 101, that may be?

[Robotbeat]

Laser still disperses at 1/r^2, but it just starts far more concentrated and the angle is much smaller for the same aperture size.

Yeah, sort of, more or less, theoretically.  Which tells us nothing as to why laser's might be preferred for such applications, why free-space communications would benefit from what they have to offer, and why they appear to be the prospective choice.  Can you say why, beyond physics/optics 101, that may be?

Yes. The half-angle of the beam is:

halfangle= 1.22*wavelength/diameterofaperture

So, the radius of the beam spot at a certain distance is just the half-angle times the distance to the transmitter.

Or rather:
beamdiameter=2*1.22*distance*wavelength/diameterofaperture

And of course, the area of the beam is just pi*(beamdiameter/2)^2, so that's where you get the 1/r^2 term (where "r" is "distance").

Doesn't matter if it's radio or visible, except that your wavelength is vastly different.

Postscript:
Same formula works for imaging. Except for transmitting (unlike imaging), you CAN'T get away with a thinned array or you end up losing all your power to the sidelobes... (For imaging, you just get a lower signal/noise ratio if you have a thinned array.)

(And this is the 101 version. The 201 version wouldn't use the small-angle approximation and would note that not ALL the beam would lie inside that area, and the 401 version would note that for imaging, this is the Rayleigh criterion and the formula makes some assumptions about signal/noise ratio, etc.)

EDIT:I flipped around the wavelength and diameterofaperture at first.

[joek]

Yes. The half-angle of the beam is:
halfangle= 1.22*diameterofaperture/wavelength
So, the radius of the beam spot at a certain distance is just the half-angle times the distance to the transmitter.
Or rather:
beamdiameter=2*1.22*diameterofaperture*distance/wavelength
And of course, the area of the beam is just pi*(beamdiameter/2)^2, so that's where you get the 1/r^2 term (where "r" is "distance").
Doesn't matter if it's radio or visible, except that your wavelength is vastly different.

Excuse me for being dense, but that assumes an uncollimated source?

[Robotbeat]

Yes. The half-angle of the beam is:
halfangle= 1.22*diameterofaperture/wavelength
So, the radius of the beam spot at a certain distance is just the half-angle times the distance to the transmitter.
Or rather:
beamdiameter=2*1.22*diameterofaperture*distance/wavelength
And of course, the area of the beam is just pi*(beamdiameter/2)^2, so that's where you get the 1/r^2 term (where "r" is "distance").
Doesn't matter if it's radio or visible, except that your wavelength is vastly different.

Excuse me for being dense, but that assumes an uncollimated source?

It assumes collimated, actually. Or you can say it assumes you're doing your best with your optics to get the beam spot as small as possible, within the constraint of having the aperture that size. Light is a wave (and so is matter, though the wavelength is generally FAR shorter for matter, which is why people use electrons for getting high resolution microscopic images).

And this is the far-field expression for spot size, where the distance (between the transmitter and receiver) is much, much greater than any of the other relevant lengths (such as aperture diameter, etc). I.e., the situation for a microscope may be somewhat different (though still pretty relevant, unless you get VERY close).

[joek]

It assumes collimated, actually. Or you can say it assumes you're doing your best with your optics to get the beam spot as small as possible, within the constraint of having the aperture that size. Light is a wave (and so is matter, though the wavelength is generally FAR shorter for matter, which is why people use electrons for getting high resolution microscopic images).

And this is the far-field expression for spot size, where the distance (between the transmitter and receiver) is much, much greater than any of the other relevant lengths (such as aperture diameter, etc). I.e., the situation for a microscope may be somewhat different (though still pretty relevant, unless you get VERY close).

Thanks (smack!... must have slept through it... time to go back and hit the books!).
Maybe the operative question is what size optics/power are required for DSI?

[mlindner]

Yes. The half-angle of the beam is:
halfangle= 1.22*diameterofaperture/wavelength
So, the radius of the beam spot at a certain distance is just the half-angle times the distance to the transmitter.
Or rather:
beamdiameter=2*1.22*diameterofaperture*distance/wavelength
And of course, the area of the beam is just pi*(beamdiameter/2)^2, so that's where you get the 1/r^2 term (where "r" is "distance").
Doesn't matter if it's radio or visible, except that your wavelength is vastly different.

Excuse me for being dense, but that assumes an uncollimated source?

It assumes collimated, actually. Or you can say it assumes you're doing your best with your optics to get the beam spot as small as possible, within the constraint of having the aperture that size. Light is a wave (and so is matter, though the wavelength is generally FAR shorter for matter, which is why people use electrons for getting high resolution microscopic images).

And this is the far-field expression for spot size, where the distance (between the transmitter and receiver) is much, much greater than any of the other relevant lengths (such as aperture diameter, etc). I.e., the situation for a microscope may be somewhat different (though still pretty relevant, unless you get VERY close).

beamDiameter = 2 * 1.22 * diameterOfAperture * Distance / Wavelength
beamArea = pi * (beamDiameter / 2)^2

So I've concluded Robobeat's math is wrong or this is impossible. So plugging in a few numbers. Assuming a 20cm aperture, satellite in earth's orbit at opposition 300 million km, assuming ~1000 nm infrared laser. This gives us a beam diameter of  0.1464 * 10^15 km or 146.4 million million km. I highly doubt the beam diameter is 6 orders of magnitude larger than the diameter of earth's orbit on the other side of earth's orbit as this breaks common sense of personal use of lasers.

[Robotbeat]

Ha! You're right! I switched around the wavelength and aperture diameter.

Always do a sanity-check, first...

https://www.google.com/search?q=2*1.22*2.5AU*1micron%2F%2820cm%29&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a

Google search for "2*1.22*2.5AU*1micron/(20cm)"
4562.73506 kilometers

Much better answer.

BTW, you can often do pretty well with just a collection of relatively common-sense assumptions and making sure the units work out (we call this "dimensional analysis"), like knowing that if your wavelength is smaller, so should be your spot size and if your aperture is bigger, you should get a smaller spot size, and the further away you are the bigger your spot size... Using just that:

spotdiameter is proportional to wavelength

spotdiameter is proportional to distance


spotdiameter is inversely proportional to aperture size

With just that information, you can get this formula:

spotdiameter = k*wavelength*distance/(aperturediameter)

where k is a proportionality constant. It turns out this is just the formula we get from the Rayleigh criterion, with k being 2*1.22 in our case.

http://hyperphysics.phy-astr.gsu.edu/hbase/phyopt/cirapp2.html#c2

[mlindner]

Ha! You're right! I switched around the wavelength and aperture diameter.

Always do a sanity-check, first...

https://www.google.com/search?q=2*1.22*2.5AU*1micron%2F%2820cm%29&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a

Google search for "2*1.22*2.5AU*1micron/(20cm)"
4562.73506 kilometers

Much better answer.

I'm completely unfamiliar with optics but isn't the half angle the angle from the center line of the beam to the edge of the beam? In that case wouldn't the radius of the beam at distance be tan(halfAngle) * distance?

[Robotbeat]

Ha! You're right! I switched around the wavelength and aperture diameter.

Always do a sanity-check, first...

https://www.google.com/search?q=2*1.22*2.5AU*1micron%2F%2820cm%29&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a

Google search for "2*1.22*2.5AU*1micron/(20cm)"
4562.73506 kilometers

Much better answer.

I'm completely unfamiliar with optics but isn't the half angle the angle from the center line of the beam to the edge of the beam? In that case wouldn't the radius of the beam at distance be tan(halfAngle) * distance?

Technically yes! But for small halfangle, tan(halfangle)= ~halfangle.

It makes very little difference, mathematically! We're talking about microradians and such, here, so they're essentially identical (beyond the limit of a hand calculator).

And I forgot to mention we were using radians... If you try this with degrees, you'll get a very wrong result.

[mlindner]

Ha! You're right! I switched around the wavelength and aperture diameter.

Always do a sanity-check, first...

https://www.google.com/search?q=2*1.22*2.5AU*1micron%2F%2820cm%29&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a

Google search for "2*1.22*2.5AU*1micron/(20cm)"
4562.73506 kilometers

Much better answer.

I'm completely unfamiliar with optics but isn't the half angle the angle from the center line of the beam to the edge of the beam? In that case wouldn't the radius of the beam at distance be tan(halfAngle) * distance?

Technically yes! But for small halfangle, tan(halfangle)= ~halfangle.

It makes very little difference, mathematically! We're talking about microradians and such, here, so they're essentially identical (beyond the limit of a hand calculator).

And I forgot to mention we were using radians... If you try this with degrees, you'll get a very wrong result.

So ~4km is roughly 1/3 the diameter of earth.
Now the next two questions are:
1) How much power density from light is reliably detectable so that if you were to modulate the beam you could detect the modulation?
2) For a benchmark, how good of pointing accuracy is possible with the best modern spacecraft? The half angle is roughly 10 micro radians. Cubesats that I've worked with have trouble getting pointing accuracy to within 1 to 0.1 degree (or 20 to 2 milli radians respectively). The best cubesats I know of (made by aerospace corp) brag about having < 1 degree pointing accuracy. We need to have 2-3 orders of magnitude better pointing for this to be possible.

[Robotbeat]

Ha! You're right! I switched around the wavelength and aperture diameter.

Always do a sanity-check, first...

https://www.google.com/search?q=2*1.22*2.5AU*1micron%2F%2820cm%29&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a

Google search for "2*1.22*2.5AU*1micron/(20cm)"
4562.73506 kilometers

Much better answer.

I'm completely unfamiliar with optics but isn't the half angle the angle from the center line of the beam to the edge of the beam? In that case wouldn't the radius of the beam at distance be tan(halfAngle) * distance?

Technically yes! But for small halfangle, tan(halfangle)= ~halfangle.

It makes very little difference, mathematically! We're talking about microradians and such, here, so they're essentially identical (beyond the limit of a hand calculator).

And I forgot to mention we were using radians... If you try this with degrees, you'll get a very wrong result.

So ~4km is roughly 1/3 the diameter of earth.
Now the next two questions are:
1) How much power density from light is reliably detectable so that if you were to modulate the beam you could detect the modulation?
2) For a benchmark, how good of pointing accuracy is possible with the best modern spacecraft? The half angle is roughly 10 micro radians. Cubesats that I've worked with have trouble getting pointing accuracy to within 1 to 0.1 degree (or 20 to 2 milli radians respectively). The best cubesats I know of (made by aerospace corp) brag about having < 1 degree pointing accuracy. We need to have 2-3 orders of magnitude better pointing for this to be possible.

Totally depends... You can technically detect a signal of just a handful of photons. This is what people do when measuring the distance to the Moon using the retroreflectors left there by Apollo. I actually don't know a handy formula relating power intensity to data rate... partially because you need to know what your noise level is going to be. If anyone does know a handy formula, it'd be appreciated!

But I think the data rate is proportional to the natural log of the signal/noise ratio, perhaps also proportional to the total power level (perhaps the natural log of it as well), and directly proportional to the "bandwidth", i.e. the amount of spectrum devoted to the communication. With light, this last one can be pretty high. Any radio engineers? Or, I guess we could google. Of course, with low light levels, you're talking about individual photons, so you have that limit, too. You can encode information in the time-of-flight of a photon (or group of photons), and the resolution of that time-of-flight will determine how much bandwidth (or rather, how much frequency spread) you are using.

I haven't taken an information theory class, otherwise I'd probably have a really good answer for you.

[Robotbeat]

Ah-HA!

http://en.wikipedia.org/wiki/Shannon-Hartley_theorem

The Shannon-Hartley Theorem says (maximum possible data rate, whatever modulation schema):

Datarate(in bits per second) = analogbandwidth(in Hertz)*logbase2(1+signalpower/noisepower)

But it's sort of difficult to use this back-of-the-napkin style, since we don't have anything good for the "noise" level... Except that it's probably pretty low... Comparable to the brightness of the asteroid we're visiting. Of course, a good way to lower the noise level is to apply a band-pass filter that will filter all light but a very narrow range of wavelengths, so that the laser light (which is very monochromatic) will be bright compared to the asteroid.

Don't forget the photon shot noise.

[Robotbeat]

Notice, much of this equation depends at least as much on your receiver as it does the transmitter.

[happyflower]

Beyond the nitty gritty details that you guys love so much to discuss (snore lol), I must admit that when DSI came out and said Asteroid 2021 DA14 is worth $200 Billion or whatever they lost most of their credibility with me anyway. I mean come on who are they talking to, children?

I mean what is the point of saying something like that? What about your costs of extraction and transportation? What about your customers? What a pie in the sky dreamers these guys turned out to be.

Oh well Still have a little bit of credibility with PR left. Lets see if they blow it or add to it.

[QuantumG]

Remember: you're not as smart as you think you are.

Assuming other people are just dumb is a good way to write off ever learning anything new.

[happyflower]

Remember: you're not as smart as you think you are.

Assuming other people are just dumb is a good way to write off ever learning anything new.

Well you didn’t explicitly say so, but since your post is right after mine I’ll assume you meant me. I don’t have to remember, I know I am not that smart. I am neither an aerospace engineer, nor a scientist, but simply a spaceflight enthusiast. By the way I didn't call or assumed anybody was "dumb".

If you mean that I should re-read DSI statement regarding this rock being worth 200 billion dollars I don’t have to. Their statement is simply wrong. It’s wrong and it makes them look less knowledgeable than they surely are.

You cannot simply calculate the cost of ore the way they did. Ore doesn’t process itself. You need workers to mine the ore, you need transportation to move the ore to processing facilities, you need processing facilities, you need security to protect your ore, and you need transportation infrastructure to get the ore to customers that need it. That final price is what you can quote minus all your expenses as value. Simply stating that a piece of rock that is hauling ass in space is worth 200 billion is just wrong. Sorry it is. Otherwise all of us on Earth are Gazillioners since the Earth is wroth a Gazillion dollars.

That rock is worth nothing as it stands right now. It’s just a rock that even DSI states they simply cannot reach even if they had everything in place. Hence “pie in the sky dreamers”.

[QuantumG]

If you mean that I should re-read DSI statement regarding this rock being worth 200 billion dollars I don’t have to. Their statement is simply wrong. It’s wrong and it makes them look less knowledgeable than they surely are.

Where did they make this statement?

Presumably you read the Forbes article:
 
   http://www.forbes.com/sites/timworstall/2013/02/13/no-asteroid-2021-da14-isnt-worth-195-billion-whatever-deep-space-industries-says/

but didn't bother following the link to The Register's article:

  http://www.theregister.co.uk/2013/02/13/dsi_places_valuation_on_2012_da14/

to see what it was that was actually quoted. The Register is such a premier bastion of journalistic integrity that they didn't even bother to say who they were quoting or where or when the speaker was speaking. I happened to recognize that they're quoting Mark Sonter speaking at the DSI press conference. I also happen to remember that the context was the distant future where in-space markets are available. The Register's article actually tries to establish that context:

Not that DSI – or anyone else, for that matter – is quite ready to mine 2012 DA14. DSI plans to send its first FireFly probes to scout Near Earth Objects (NEOs) in 2015, to be followed by larger DragonFly probes in 2016, which will sample NEOs and return their booty to Earth, followed by actual mining operations beginning in 2020 – if all goes according to their ambitious plans, that is.

and even provides a breakdown of how the future in-space markets might make use of the material:

"According to DSI experts," those experts humbly contend, "if 2012 DA14 contains 5 per cent recoverable water, that alone – in space as rocket fuel – might be worth as much as $65 billion. If 10 per cent of its mass is easily recovered iron, nickel and other metals, that could be worth – in space as building material – an additional $130 billion."

The Forbes article is written by someone who read the first two paragraphs of The Register's article and then rushed off to write something derogatory and disingenuous.

[happyflower]

Well I was speaking for myself and I am still not sure what part of what I wrote is wrong. I have done enough business development that when a company makes such claims that I can see are not attached to current reality I tend to hold them suspect. It has saved me and the company I work for a lot of time and money. If they were talking hypothetically and in a possible future then great.

All I can say is I hope whoever makes $200 Billion from this rock, today or tomorrow or whenever enjoys their money in good health.

With your permission I wont hold my breath.

[QuantumG]

Well I was speaking for myself and I am still not sure what part of what I wrote is wrong.

Your claim that they said something they never said.

[happyflower]

Well I was speaking for myself and I am still not sure what part of what I wrote is wrong.

Your claim that they said something they never said.

http://www.space.com/19758-asteroid-worth-billions-2012-da14-flyby.html

"The space rock set to give Earth a historically close shave this Friday (Feb. 15) may be worth nearly $200 billion, prospective asteroid miners say."

"may harbor $65 billion of recoverable water and $130 billion in metals, say officials with celestial mining firm Deep Space Industries. "

""Deep Space Industries is being far too optimistic about this particular rock," Michael Busch, of the National Radio Astronomy Observatory, told SPACE.com via email."

"Nick Moskovitz at MIT has obtained an IR spectrum of DA14, and it is an L-class object," he added. "That means a stony composition, made of iron-magnesium-silicates, and minimal water and accessible metal content. It also is not obvious how much the value of water and metal in Earth orbit would decrease with an increased supply."

"The company has no plans to go after 2012 DA14; the asteroid's orbit is highly tilted relative to Earth, making it too difficult to chase down. But the space rock's close flyby serves to illustrate the wealth of asteroid resources just waiting to be extracted and used, Deep Space officials said."

[mlindner]

Well I was speaking for myself and I am still not sure what part of what I wrote is wrong.

Your claim that they said something they never said.

http://www.space.com/19758-asteroid-worth-billions-2012-da14-flyby.html

"The space rock set to give Earth a historically close shave this Friday (Feb. 15) may be worth nearly $200 billion, prospective asteroid miners say."

"may harbor $65 billion of recoverable water and $130 billion in metals, say officials with celestial mining firm Deep Space Industries. "

""Deep Space Industries is being far too optimistic about this particular rock," Michael Busch, of the National Radio Astronomy Observatory, told SPACE.com via email."

"Nick Moskovitz at MIT has obtained an IR spectrum of DA14, and it is an L-class object," he added. "That means a stony composition, made of iron-magnesium-silicates, and minimal water and accessible metal content. It also is not obvious how much the value of water and metal in Earth orbit would decrease with an increased supply."

"The company has no plans to go after 2012 DA14; the asteroid's orbit is highly tilted relative to Earth, making it too difficult to chase down. But the space rock's close flyby serves to illustrate the wealth of asteroid resources just waiting to be extracted and used, Deep Space officials said."

There is a difference between the words "if" and "may." I suggest you re-read what QuantumG quoted and see how it disagrees with what space.com stated.

[WiresMN]

You cannot simply calculate the cost of ore the
way they did. Ore doesn’t process itself. You need
workers to mine the ore, you need transportation to
move the ore to processing facilities, you need
processing facilities, you need security to protect
your ore, and you need transportation
infrastructure to get the ore to customers that need
it. That final price is what you can quote minus all
your expenses as value. Simply stating that a piece
of rock that is hauling ass in space is worth 200
billion is just wrong.

The monetary worth of this rock has nothing to do with the operational cost of extraction. It may be worth 200 billion, but it may cost more than that to extract. This happens all of the time in mining. The Backken oil field in North Dakota is only viable because oil is expensive.

If DSI is using similar calculations as PRI then it might be worth that much if it was available. PRI bases water price on the cost of launching it. Both companies are working on long timelines, 10 years on the extremely optimistic estimate. In that time we will hopefully have a need for water in large quantity in space.

Furthermore, during that time the platinum group metals are not going to go down rather they will go up due to higher usage. The same rock they estimate at 200 billion today could be worth a lot more in 10-20 years.

But really what the did was pick a rock that was getting media attention and spin the news to explain what they are about and why they are trying to mine asteroids. should they have said we plan to mine asteroids like the one zipping by earth.... but hey it has no value to anyone. Are you interested in our company?

[happyflower]

mlindner, to me the issue really isn’t ‘if’ or ‘may’. It’s not whether “if” this asteroid is worth $200 B. or this asteroid “may” be worth @200 B. The issue I have is the $200 Billion figure.

QG said “Your claim that they said something they never said”. Well what did I say that they never said? All I said is that DSI said this rock is worth $200 B. I showed him where I got my statement from.  After all $65 billion plus $130 billion is about $200 billion.

My statement was simply that value is not proven with any type of data and is a gross value anyway. You cannot as a company and in good conscious quote a gross number to people as the value without discussing your costs. If you just throw a number like $200 Billion around like pasta and see if it sticks you will lose a lot of credibility in the business world. Look I work in marketing and bus. Dev. And I understand making statements that will excite people and cause discussions and eyeballs on your site. Like WiresMN I think that’s all this was, but that sort of goes towards my conclusion.

I think I made a fairly reasonable conclusion based on what I read. If Space.com or Forbes, or theregister, or National Radio Astronomy observatory, or MIT have made false statements or misrepresented DSI in anyway then I guess they will have a lawsuit on their hands.

I could be proven wrong (and I will be happy to see DSI make 200 Billion now or in the near or far futures) and then I will retract my statement and take my lumps. Until such time I’ll stick with my conclusion which is simple: DSI has lost credibility to me. I still wish them all the success because it makes me happy to see US private companies working in space. I guess we will see.

[Carl G]

Stupid thread, with biased people making misrepresentations.

Locked.