NASA wants to catch, return asteroid

[A_M_Swallow]

{snip}

The de-spinning task is just attitude control starting with high initial angular velocities.  There is some question about how much power your solar panels would produce while spinning, but lower power (above a tiny threshold) just means it takes longer to de-spin.

If there is going to be power problems put the solar panels on slip rings like radar heads.

[HappyMartian]

....
Exactly.

They simplify their analysis because they're taking a first stab at solving a very difficult problem. 
....

Great post John! Remind me to avoid arguing with you!

[JohnFornaro]

no point in getting super-detailed with hypotheticals

Actually, there is a point.  Getting $2.6B, at the least, in taxpayer financing.   If they can get that while also glossing over the hypotheticals, they will be assuredly having a drink with Lori Garver after work on some given Friday.

[JohnFornaro]

X tonnes of water could have plenty of uses.

As a general reminder, that's "x" tons of water at an L-point of one's choosing. 

I'm saying that "x" is "planned" to be 100 tons of water, as per the Keck mission conjecture.  What "x" were you thinking of?

[KelvinZero]

Hi guys,
I think we are still really comparing captured asteroid to lunar architecture so I have made a thread here:
http://forum.nasaspaceflight.com/index.php?topic=31701.0

[a_langwich]

No doubt that the problem of despinning the asteroid could be solved.  You can see the necessary complexity involved.  When you see complexity, you also see cost.

From their budget numbers, they've allocated $223.5M for propulsion systems, of which the RCS system is a part, I'm guessing.  Who knows what proportion of that line item pertains to RCS.  Again, remember that somebody else is bearing the costs of bringing this novel RCS system to TRL-6.

You can't dig any deeper into the Keck paper than this, however.

I'm really tired of this.  At this point it's clear your criticisms are your unshakeable premise, not a conclusion.  I'm not sure if you don't have the technical background to understand what's really difficult vs what might seem difficult, or if it's just stubbornness.

Here's a relevant quote from the Keck paper:
http://www.kiss.caltech.edu/study/asteroid/asteroid_final_report.pdf

The GNC algorithms to rendezvous with a non-cooperative space object exist for objects in Earth orbit. The algorithms, developed for rendezvous and sample capture, were exercised in a DARPA funded study. That study demonstrated the capture of a defunct, spinning and wobbling, non-cooperative object in Earth orbit.

There.  Done. 

Exactly.  They are referring to trajectory and burn timing as you reaffirm.  The resemblance to Dawn is only superficial concerning these two requirements.  What's not superficial is the mass of an 1100 ton tumbling object, and the resulting necessary cost of retrieving that honker.  This, they continue to estimate, holding up instead superficial similarities, which are easy for congress critters to gloss over.

1.  Shrug off explanation to question (must have been rhetorical).
2.  Beg the question.
3.  Conspiracy explanation.

It is entirely appropriate, when talking about a trajectory design for SEP propulsion, to refer to a previous, though smaller, SEP propulsion mission and how its trajectory worked.  You are making a stupid argument here, based on the logical fallacies listed above, and because you are combing the report for things to attack.  Perhaps you are trying to score rhetorical points, but you are shooting own goals. 

Again, I do not complain about the theoretical technical feasibility.  I complain about the false costing, the sketchy prioritization; the timliness; the actual benefit of a hoped for 100 tons of water; yada yada.

The false costing, we've previously discussed:  at first it was your demand they include all sorts of other projects under this budget (SLS, DSH, CPS, ISRU, etc), possibly because you didn't understand the scope of their project and were confusing the Keck Institute with NASA, unmanned with manned, and asteroid retrieval with things that might be useful once we have an asteroid.  Then, the false costing became about details that you have decided must be 10-20x as expensive, either because you don't understand how they propose to do them or because you have pre-decided "false costing" and had to make it so.  You've quoted another poster who was complaining about them adding a 30% project reserve on top of an ML cost estimation, as if that supported your contention they were horribly lowballing cost estimates. 

The "actual benefit of a hoped for 100 tons of water" demonstrates that you have managed to shed any understanding of what the Keck Institute report was about, which is quite remarkable and sad after spending the time to mine quotes for your points.

The "sketchy prioritization" is I think the real reason for all this obtuseness.  Apparently whatever option you hoped to see has gotten pushed aside, at least in your mind, for something along the lines of this Keck study.  Good thing for you there is almost zero chance that NASA will continue on this same path for the next eight to ten years.  Bad thing is there is also zero chance NASA would stay focused on your preferred option, as well, if they ever chose it.

And whatever option you wanted to see pursued, unless you want to ditch manned spaceflight entirely, would benefit enormously from that "100 tons of water."  Both in learning how to get it, and having it available.  Neither of which are in the scope of the Keck Institute project, which I'll point out one last time was about an unmanned asteroid capture and retrieval mission.

[HappyMartian]

....

The "sketchy prioritization" is I think the real reason for all this obtuseness.  Apparently whatever option you hoped to see has gotten pushed aside, at least in your mind, for something along the lines of this Keck study.  Good thing for you there is almost zero chance that NASA will continue on this same path for the next eight to ten years.  Bad thing is there is also zero chance NASA would stay focused on your preferred option, as well, if they ever chose it.

And whatever option you wanted to see pursued, unless you want to ditch manned spaceflight entirely, would benefit enormously from that "100 tons of water."  Both in learning how to get it, and having it available.  Neither of which are in the scope of the Keck Institute project, which I'll point out one last time was about an unmanned asteroid capture and retrieval mission.

Yep, "Good thing for you there is almost zero chance that NASA will continue on this same path for the next eight to ten years. Bad thing is there is also zero chance NASA would stay focused on your preferred option, as well, if they ever chose it."

Trust is the real issue.

Trust is lacking in the current President's leadership of NASA.

Trust is lacking in the next President's leadership of NASA, and the one after that one, too.

An asteroid with lots of available ISRU water could be placed in a stable high Lunar orbit and the next President could decide we should just ignore it for forty years, like we continue to do with the Moon despite the presence of an enormous amount of polar water and other valuable resources, and continue to concentrate our human spaceflight efforts in LEO and perhaps planning for eventual Ceres missions...

Zigging and zagging Presidential orders for illogical NASA 'space plans' won't rebuild trust.

How do you rebuild trust?

[JohnFornaro]

At this point it's clear your criticisms are your unshakeable premise, not a conclusion.

Bingo.

Shake the premise of false costing then.  This has been the first problem I raised with the Keck paper.  My $46B guesstimate is based on the current JWST cost factor.

Don't bring up conspiracies either.  It is perfectly legal for the executive and legislative branches of government, or their petitioners, to falsly present costs.

Feel free to continue the "obtuse" ad hominems.  We all remember one of your earlier talking points that I haven't planned out in detail my schedule for 2021-2025.

By all means, avoid the points I raise.  Please, beg any questions that you might not prefer to answer:

What's not superficial is the mass of an 1100 ton tumbling object, and the resulting necessary cost of retrieving that honker.

2.  Beg the question.

Trajectory and burn timing are superficial similarities between Dawn and the asteroid heist, when compared to the mass, complexity, timing, and utility of the heist.  It's clear who is begging, particularly on the issue of cost.  It is true that we've "previously discussed" false costing, but not to mutual satisfaction; they are still false costs.

The Keck study proposes a narrowly defined mission, which cannot be carried out at all, without billions of dollars of necessary ancillary Design, Development, Testing & Evaluation of a host of technologies and capabilities.  I haven't "pre-decided" false costing.  The asteroid huggers are offering it.

...the scope of the Keck Institute project, which I'll point out one last time was about an unmanned asteroid capture and retrieval mission.

The asteroid heist mission as proposed by Keck cannot stand on its own merits, because it is completely dependent on many other programs which must pre-exist well in advance of any work being started on the Keck mission.  These other programs must be funded before the Keck mission should be funded.  Where's the money coming from?

**********************************

A bit of background by two noted observers who by no means agree with me on other subjects:

As Jon Goff mentioned:

But somewhere along the process, that idea seemed to go off the rails. Instead of NEOs being a quick "target of opportunity" that could be visited cheaply along the way to the Moon and eventually Phobos, Deimos, and Mars, you started seeing concept architectures coming out of NASA for these massive NEO mission stacks complete with four or five new pieces of expensive in-space hardware that needed to be developed (a Hab module, an MMSEV, a CPS, a big solar electric tug or two, etc, etc) just to visit a NEO.

Part II of the hearing on the thread from asteroids and meteors is now archived here:

There was apparently a point where a congressman asked all three presenters about the asteroid retrieval mission, got succinct answers, and then yielded his time back to the chair. The comments are probably worth repeating here.

Can you give a sentence or two summary?

Rough summary:

Q: Did you have any input into the development and selection of this mission?

A: No.

(Apparently all three of them were asked the same question and answered the same way.)

**********************

Finally, a silver lining:

It's just occurred to me that this asteroid retrieval mission seems like a great candidate for a payment-on-delivery contracting model.

Now that is a good idea.

[Robert Thompson]

http://www.spacepolicyonline.com/news/gerstenmaier-elucidates-concept-of-asteroid-return-strategy
Gerstenmaier Elucidates Asteroid Return Strategy
Posted: 20-Apr-2013
Updated: 21-Apr-2013 12:12 AM

"He suggested that the mission should be considered a success even if no capture is possible because it will have demonstrated, at a minimum, high power (40 kilowatt) solar electric propulsion." ...

"At both meetings, he said that it would almost be better if they could not find an asteroid to be in place by 2021 since that would be "pretty aggressive" to do on the first flight of a new spacecraft.  He added that the idea is for the astronauts to make two spacewalks to the asteroid, but they will not be "sophisticated" spacewalks, just an opportunity for the astronauts to "reach out and grab something" wearing slightly modified launch and reentry spacesuits." ...

"All in all, however, the White House and NASA may be exacerbating the challenge of winning support from Congress and other stakeholders.  Some officials are using imprecise terminology, there is confusion over the relationship of this mission to protecting Earth from asteroids as well as why about humans are needed to bring back a sample of an asteroid when NASA already is building a robotic probe (OSIRIS-REx) to do that (not to mention that Japan already has done so and is planning a second mission), and the budget is murky in the short term and lacks credibility for the long term."

[JohnFornaro]

He suggested that the mission should be considered a success even if no capture is possible because it will have demonstrated, at a minimum, high power (40 kilowatt) solar electric propulsion. ...

...and the budget is murky in the short term and lacks credibility for the long term.

Since capture isn't necessarily an option, they could save a billion dollars or more by not developing the bag-itecture from TRL1 to full scale working mission hardware, and call it an SEP demonstration.

The mission is a success even if it doesn't attain its primary goal?  But we should do this anyway because somehow, that the budget is "murky" and "lacks credibility", should not stop this mission from going forward?

Does anybody else get the impression that nonsense is being spouted? 

[sdsds]

http://www.spacepolicyonline.com/news/gerstenmaier-elucidates-concept-of-asteroid-return-strategy
Gerstenmaier Elucidates Asteroid Return Strategy
Posted: 20-Apr-2013
Updated: 21-Apr-2013 12:12 AM

One point Gerstenmaier stressed, however, is that this mission would change the paradigm of human spaceflight because once launched the crew would not be able to return to Earth for nine days.

What type of trajectory is that?

[HappyMartian]

He suggested that the mission should be considered a success even if no capture is possible because it will have demonstrated, at a minimum, high power (40 kilowatt) solar electric propulsion. ...

...and the budget is murky in the short term and lacks credibility for the long term.

Since capture isn't necessarily an option, they could save a billion dollars or more by not developing the bag-itecture from TRL1 to full scale working mission hardware, and call it an SEP demonstration.

The mission is a success even if it doesn't attain its primary goal?  But we should do this anyway because somehow, that the budget is "murky" and "lacks credibility", should not stop this mission from going forward?

Does anybody else get the impression that nonsense is being spouted? 

Yes.

[HappyMartian]

http://www.spacepolicyonline.com/news/gerstenmaier-elucidates-concept-of-asteroid-return-strategy
Gerstenmaier Elucidates Asteroid Return Strategy
Posted: 20-Apr-2013
Updated: 21-Apr-2013 12:12 AM

One point Gerstenmaier stressed, however, is that this mission would change the paradigm of human spaceflight because once launched the crew would not be able to return to Earth for nine days.

What type of trajectory is that?

Any trajectory but one aimed at Lunar orbit?

The Moon is a no go place. I wonder why...


Edited.

[Ben the Space Brit]

http://www.spacepolicyonline.com/news/gerstenmaier-elucidates-concept-of-asteroid-return-strategy
Gerstenmaier Elucidates Asteroid Return Strategy
Posted: 20-Apr-2013
Updated: 21-Apr-2013 12:12 AM

One point Gerstenmaier stressed, however, is that this mission would change the paradigm of human spaceflight because once launched the crew would not be able to return to Earth for nine days.

What type of trajectory is that?

I'm guessing it's a direct insertion to EML-2 rather than the previously-assumed lunar slingshot (during which burning the Orion's engine dry could abort back to Earth).

That said, I think NASA are scrambling to somehow redress what is a cis-lunar make-work mission as 'deep space' by deliberately ramping up the risk, at least at the 'discussion' stage.  The not-strictly-necessary direct insertion would be the first piece to be surrendered to make it look like they're making concessions.

[MP99]

http://www.spacepolicyonline.com/news/gerstenmaier-elucidates-concept-of-asteroid-return-strategy
Gerstenmaier Elucidates Asteroid Return Strategy
Posted: 20-Apr-2013
Updated: 21-Apr-2013 12:12 AM

One point Gerstenmaier stressed, however, is that this mission would change the paradigm of human spaceflight because once launched the crew would not be able to return to Earth for nine days.

What type of trajectory is that?

I'm guessing it's a direct insertion to EML-2 rather than the previously-assumed lunar slingshot (during which burning the Orion's engine dry could abort back to Earth).

Not EML-2. (The Keck study wasn't to EML, either). I believe this is to make sure it safely disposes onto the Moon without intervention.

Fundamentally, the idea is to send a solar electric-powered robotic spacecraft to capture a 5-7 meter diameter, 500-1,000 metric ton asteroid and put it on a course that will place it in a retrograde orbit around the Moon.

(My highlight)

I presume the 9-day trajectory is to get Orion into that retrograde orbit.

If you assume a 3-day return, that's perhaps a 6-day outbound leg?

cheers, Martin

[Robert Thompson]

John, go check out the arguments in today's thespacereview article.

[JohnFornaro]

So, Mr. Bolden sez:

"This (1) mission raises the bar for human exploration and discovery, (2) helps us protect our home planet, and (3) brings us closer to a human mission to an asteroid."

1,2,3 in that order.  No it doesn't.  Not really. Only marginally.

But what else can he say?

In the 2009 BD example given by Gerst, we build a spacecraft and launch it by 2018, 5 years from now.  2 years to get there.  3 years to bring it back, and a year to get its new orbit organized.  In eleven years, we'll get a chance to check it out, up close and personal for... wait for it... eight hours.

Just think of the children ... I mean, the science!

Of course, Mr. Gerstenmaier, has been instructed to say that with a straight face, and apparently he does.  Still, NASA needs plausible deniability: "This object [2009 BD] is not the object", we are told.

Jeff Foust notices that "there is no known small near Earth asteroid that meets the size and orbit criteria to support a 2021 crewed mission," but the authority disagrees:  Apparently there are "about 300 near Earth asteroids with diameters of approximately 10 meters, of which 13 have suitable orbits", even though they couldn't see the Chelyabinsk meteor, which clocked in at 17 meters in diameter.

NASA is spouting nonsense regarding this mission.

Of course, I'm always ready to laugh to keep from crying:   "National Research Council report on NASA’s strategic direction (see "What’s the purpose of a 21st century space agency?", The Space Review, December 17, 2013)."  I haven't had a chance to read it yet, because the calendar on my planet is stuck in April, 2013.  But hey.

[HappyMartian]

"'It brings together the best of NASA’s efforts in all areas to achieve the president’s goals faster and cheaper.'"

From: To catch a planetoid   By Jeff Foust    April 22, 2013
At: http://www.thespacereview.com/article/2283/1

Presidents propose, Congress disposes. Who's opinion is more important in setting wise goals?


Edited.

[Proponent]

Fundamentally, the idea is to send a solar electric-powered robotic spacecraft to capture a 5-7 meter diameter, 500-1,000 metric ton asteroid and put it on a course that will place it in a retrograde orbit around the Moon.

(My highlight)

I presume the 9-day trajectory is to get Orion into that retrograde orbit.

If you assume a 3-day return, that's perhaps a 6-day outbound leg?

I don't think the retrograde orbit is a big deal.  That's what Apollo used.

Per the attached paper (see Fig. 11 and focus on the curve for a circum-lunar trajectory with co-rotational injection), the round-trip time on a co-planar free-return trajectory with a perilune of 20,000 km (a guess as to how high the asteroid's high lunar orbit might be) is about 210 hours, or about nine days.  (And, by the way, the times on the outbound and inbound legs are very similar.)  That's my guess as to where the nine-day figure comes from.

If my guess is right, though, then I wonder why you wouldn't send Orion on a trajectory with a low perilune, like 100 km, brake into a 100 x 20,000 km orbit, then circularize at 20,000 km.  That way the free-return round-trip time would be shorter (an Apollo-like sixish days) and I would think you'd need less delta-V, thanks to the Oberth effect.

BtW, I'm assuming the asteroid is in a nearly equatorial lunar orbit.

[ChileVerde]

"This object [2009 BD] is not the object", we are told.

I, for one, am delighted that NASA now treads the Tao.

"The Tao that can be told is not the true Tao."

If I need a new .sig I'll consider that.

Edit: 道可道非常道