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#20 by veblen on 01 Apr, 2014 17:42
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Good article, stupid mission. Does not capture public imagination, will end up in the pile of powerpoints on the side of the road after the next budget cut.
Cute cat vids are popular. Kittys in micro-gravity would be hysterical and I dare say, "capture public imagination". Is that a good basis for designing space missions? -
#21 by Space Ghost 1962 on 01 Apr, 2014 18:50
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Excellent article - head and shoulders better than any I've read on the subject.
Too bad it's apparently not being read by some of the posters critically but being reacted to. And one should read more of the supporting materials before responding with predictable "knee jerk" agendas. If the critical posts above carefully examine the article that was carefully written, they'll find it addresses the issues they bring up. I find that very annoying.
As I see it, the reason for this mission being separated from a SLS EM-2 (or other) is manifold - there are many political contradictions involved here that get dealt with all in one. That is the overriding consideration, and it's a smart one.
Few of you will agree with the reason SLS is being built - to provide a "credible threat" of doing human exploration beyond LEO such that at any time, any future "space race" that might be attempted, means that the US could adapt and respond in time to matter. We'll ignore the practical (and political) aspects that limit this pragmatism of which I have considerable doubt. Realize SLS does not have to be "used" but "useful". It actually helps that it is expensive, huge, and difficult to manage ... because only China and Russia would ever dare do something like it, and only then at a extreme cost.
The key problem with the prior mission involving SLS was that it confused a real exploration and capability development with this agenda, which must remain "pure" for political reasons. Among them is the ability to leave unresolved the deployment of SLS with its huge operational cost burdens. Remember, SLS is a strategic threat, not a tactical/operational capability.
In the past, such impurities were allowed. But now the fear is diversion of resources in any form such that the agenda is potentially compelled in any fashion. This is also why things appear so ridiculously impractical, and why so much antagonism results among those in these community - they have little to agree with unless its all one way.
We are moving into a more precarious world given recent events, and certain national security issues require a different posture than before. It is best to keep a tight definition on roles and need, irrespective of minor agendas being battled for by advocates.
Sooner or later you'll need to point SLS/Orion at something, and do some real science. Original EM-1/2 are embarrassing missions for NASA and are "impure" because of the contradictions that the guardians of purity have created for themselves.
This smart move allows them to exit the corner they've painted themselves into. Also, it means extending the beginnings of a defense capability started with the Deep Impact and Stardust missions as a US only research and development mission, albeit small scale. It also exposes the competitive aspect of all the players to respond, which leverage’s US economic and technological skills effectively.
Don't get distracted by the "noise" here - that a 100 meter asteroid isn't a 3,476,000 meter Moon. Listen to the "signal" - total control, access both human and robotic, by commercial industry and government science/military/other. Cheap by the standards of per square meter or ton of exploration.
Do we really know everything about Morro Rock? Can we toss it around at kilometers/sec? Do we understand the geology, formation, volatiles, metals, etc of it? Answer: No
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#22 by yg1968 on 02 Apr, 2014 00:36
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Good article!
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#23 by jongoff on 02 Apr, 2014 02:08
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Have they considered a direct mechanical coupling, perhaps like Altius' "Sticky Boom" and/or a drill-like component to grasp onto the object and secure it to the spacecraft? This seems more feasible to scale up for a future planetary defense asteroid deflection system. The bag approach seems like a dead end in terms of scale.
I think different tools make sense at different scales. If you can be relatively sure that your target is solid rock, using something like the JPL microspines technology that they've been looking at, coupled with some arms (I'm partial to our boom technology but there is more than one way to skin a cat) makes a lot of sense. But if your target is a complete asteroid, that might be a rubble or even dust-pile, you're only going to bring it home with some variant on the bag concept (which provides very distributed forces and containment), or deflect it with a gravity tractor or their Ion Beam Deflection technique.
It was neat to see the details. We've worked with the JPL lab doing the microspines work.
Unfortunately for the BAA, they won't let proposers use NASA or JPL team members *or* technology. So microspines are out for proposers. But we have some ideas. I'm hoping to put in a proposal or two.
~Jon -
#24 by jongoff on 02 Apr, 2014 02:11
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Am I missing something or are we reaching a point when it might jsut be better to go out and visit an asteroid? Adding three years adds three more years worth of budget in addition to the $2 or so billion you save by not developing the retrieval element. That may be enough to develop a deep space mission/habitat module. The LUS will increase SLS's throw weight so much that two Block 1B launches will throw as much as three Block 1s to BEO. The 2021 SLS launch with the ICPS could still be used as a shake down cruse to check Orion and most of SLS out.
The problem is that Orion as-is doesn't have a heat shield that can survive return from most asteroids. The may be able to improve it a bit around the edges, but if they end up going to a new heat shield material (which is just about 100% guaranteed for Mars-return capability), requalifying that at this point could be really expensive. Orion and SLS just aren't good tools for BEO exploration. They might be ok for the Moon and the L-points, but they're the totally wrong tools for the job for other destinations. This isn't a slam on them--they were original designed with lunar missions in mind. The problem was when the mission changed, instead of recompeting the solutions, they just remarketed them, without actually making sure they had the required capabilities.
~Jon -
#25 by jongoff on 02 Apr, 2014 02:12
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Again, a good update, but we should be careful when making absolute statements or making claims about supposed planetary defense capabilities.
It's in the presentations. This is a write up of the presentations. I suggest you read them.
Yeah, the presentations were actually a lot of great detail. The JPL and Langley teams are no slouches. I think the concepts *can* be improved on, but they didn't leave a ton of low-hanging-fruit. :-)
~Jon -
#26 by Proponent on 02 Apr, 2014 15:37
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Am I missing something or are we reaching a point when it might jsut be better to go out and visit an asteroid?...
The problem is that Orion as-is doesn't have a heat shield that can survive return from most asteroids....
In addition, Laurie Garver mentioned in an interview shortly before leaving NASA that the doctors were not ready to approve a many-month BEO mission at this stage. -
#27 by redliox on 02 Apr, 2014 16:16
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Here's a thought applicable toward the boulder-retrieval version of ARM: could it pickup the Phobos "monolith"?
If I recall the load charts right, carbonaceous targets are the variety ARM can hoist the most with. I imagine this this would be toward the heavier end of even those limits, but outside of a boulder from Olympus Mons itself this thing would be an excellent consolation price to haul back from Mars.
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#28 by Proponent on 02 Apr, 2014 16:27
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Getting to Phobos and back would require quite a bit more time and delta-V than going to a carefully-selected NEA.
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#29 by laszlo on 02 Apr, 2014 16:42
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Good article, stupid mission. Does not capture public imagination, will end up in the pile of powerpoints on the side of the road after the next budget cut.
Cute cat vids are popular. Kittys in micro-gravity would be hysterical and I dare say, "capture public imagination". Is that a good basis for designing space missions?
For a purely commercial mission, yes. NASA, of course, is where the pre-commercial stuff is supposed to get done. Unfortunately, their funding comes from the public purse, so unless there's enough level of public engagement to get Congress' attention, missions will die, like Apollo did.
My concern is that this mission makes no sense. If you're going to robotically fetch a big rock, why leave it way out there where you then have to stage an expensive manned mission to have astronauts crawl all over it? Wouldn't it make more sense to bring it to the ISS? Or, since the mission has turned from exploration to studying rocks, why not just look at the pieces of asteroids that have voluntarily come to Earth?
Real manned asteroid exploration is getting into a spacecraft and going out to an asteroid. That's a mission that would get peoples' interest.
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#30 by aero on 02 Apr, 2014 18:15
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How much additional delta V would the system need to have in order to bring the asteroid back to the ISS instead of dropping it off at the current planned orbit? Would a refueling mission be enough extra prop to bring it down low.
After all, they are not talking about a big, dangerous asteroid. Of course I know it all depends on the mass of the captured asteroid. -
#31 by metaphor on 02 Apr, 2014 19:56
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How much additional delta V would the system need to have in order to bring the asteroid back to the ISS instead of dropping it off at the current planned orbit? Would a refueling mission be enough extra prop to bring it down low.
After all, they are not talking about a big, dangerous asteroid. Of course I know it all depends on the mass of the captured asteroid.
If not using aerocapture or aerobraking, it would take about 4000 m/s of delta-v to get to LEO. The spacecraft is designed to use about 200 m/s of delta-v from the time it captures an asteroid to lunar orbit. If the asteroid was 50 tons or less, the spacecraft might have enough delta-v to get to LEO. But it would be out of the question for a 500-ton asteroid (you would need a spacecraft 10 times bigger).
From an ISRU point of view, it makes no sense to drag the asteroid down the gravity well into LEO, only to have to go back out afterwards. -
#32 by clongton on 02 Apr, 2014 20:28
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Two related questions:
1. What is the expected SCIENCE return from this retrieval mission? Bringing back a rock to analyze does not really count because learning anything new about the rock beyond what spectral analysis shows is highly unlikely.
2. Assuming there is a real science return, is it worth it in terms of the cost of getting it?
I have yet to see this question directly answered. -
#33 by notsorandom on 02 Apr, 2014 20:30
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This would be in 2024, ten years from now. Several year long stints at ISS would have been completed. Also this would be ten years after EFT-1. Should be long enough to have figured the heat shield out.Am I missing something or are we reaching a point when it might jsut be better to go out and visit an asteroid?...
The problem is that Orion as-is doesn't have a heat shield that can survive return from most asteroids....
In addition, Laurie Garver mentioned in an interview shortly before leaving NASA that the doctors were not ready to approve a many-month BEO mission at this stage. -
#34 by Robotbeat on 02 Apr, 2014 22:52
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Two related questions:
VERY untrue.
1. What is the expected SCIENCE return from this retrieval mission? Bringing back a rock to analyze does not really count because learning anything new about the rock beyond what spectral analysis shows is highly unlikely....
My former adviser does sample analysis on extra-terrestrial samples, and there is an enormous, ENORMOUS amount of other stuff you can do besides just spectral analysis. It's like saying you don't need to meet a person, just read their signature.
Extraterrestrial samples that come from a known asteroid are worth a lot scientifically, that's why we do sample return missions like OSIRIS-REx. That said, I asked him about whether he'd like 5 small samples (i.e. tens of grams) from 5 different targets versus 1 very big group of samples (100s of kg) from a single target, and he said he'd prefer the 5 different samples from 5 targets, although he had to think about it for a bit. Then again, he usually works with microscopic sample sizes. Others methods of study require larger samples. But still, OSIRIS-REx has a total cost of about $1 billion. If I had to guess, I'd say the asteroid return is probably worth a good two OSIRIS-RExes, so maybe about $2 billion. Not enough to justify the whole expense, but perhaps enough to justify the cost of the unmanned capture vehicle itself. -
#35 by Remes on 02 Apr, 2014 22:59
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1. What is the expected SCIENCE return from this retrieval mission? Bringing back a rock to analyze does not really count because learning anything new about the rock beyond what spectral analysis shows is highly unlikely.
The idea is, that some asteroids were created at the same time as our solar system. Therefore the content of the asteroid is very much the same as earth a few billion years ago. It would allow scientists to check their models, assumptions, understand formation of planets... it would allow science to understand what was earth based on the solar system and what parts on earth were brought in by impacting asteroids. So, even if it is a ball of dirt, it still can teach us a lot of the beginnings of the solar system, as this ball of dirt is some kind of snapshot. It's like digging ice cores in the antarktis to see, what earth's atmosphere was xyz years ago.Quote2. Assuming there is a real science return, is it worth it in terms of the cost of getting it?
Well, it depends on what scenario you choose. Rosetta, Hayabusa, Star Dust, ... I think every dollar/yen/euro was worth it. As we all know, the spacecraft flew to the asteroid. It's like understanding that, if someone wants a glass of milk, he doesn't need to bring the cow into his living room.
Some might say that an asteroid retrieval mission is like an asteroid collision avoidance training. Well, IMHO it would be enough to prove, that a given delta-v can be applied. Where this happens, doesn't matter.
In regards of HSF: for the sake of science there is zero added value if a human chops of some dirt from the asteroid. Zero! It increases cost dramatically (I guess by magnitudes). A geologist will have to look which part of the asteroid will be picked, but he can do that remote via TV. Really, sending humans to an asteroid is not done for science. There might be a need to drill a whole, but that can be done by machines and anyway: no one wants to have an Astronaut next to a sharp rotating tool in space.
Now there is SLS, and SLS is about humans in deep space. If people agree, that there is no benefit for science if humans do the work, that the costs are okay and it is mainly about training people, testing SLS, Orion, ... , than I guess the decission is made.
In terms of science, I think, it would be better to do sample return mission over a couple of different asteroid types. Samples must be examined on earth, only here the full spectrum of spectrometers and tests can be applied. An astronaut next to the Asteroid will do exactly 0.0 science.
I like to see science done on asteroids and I like to see SLS launch and humans in deep space. But combining these two will be hard to explain to the mass of people. -
#36 by clongton on 02 Apr, 2014 23:48
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But still, OSIRIS-REx has a total cost of about $1 billion. If I had to guess, I'd say the asteroid return is probably worth a good two OSIRIS-RExes, so maybe about $2 billion. Not enough to justify the whole expense, but perhaps enough to justify the cost of the unmanned capture vehicle itself.
But I asked about the "mission", not just the capture spacecraft. To get mission cost you have to add the cost of the SLS HLV launch vehicle and the cost of the launch. That totals quite a but more than $2b total. That's where I'm going with this. That is a lot of money for a single mission. Can this be done with a different, less expensive vehicle, say a Falcon Heavy or a Delta IV Heavy for example? At least then there is an effort to contain costs instead of finding a mission for a seldom used HLV. -
#37 by Vultur on 03 Apr, 2014 01:47
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Am I missing something or are we reaching a point when it might jsut be better to go out and visit an asteroid?...
The problem is that Orion as-is doesn't have a heat shield that can survive return from most asteroids....
In addition, Laurie Garver mentioned in an interview shortly before leaving NASA that the doctors were not ready to approve a many-month BEO mission at this stage.
The problem with this is that unless we actually do it, it'll always be "at this stage" -- we've been messing around in LEO for decades supposedly to learn how to do BEO.
It's time to just develop the habitat, and DO IT. IMO.
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#38 by Coastal Ron on 03 Apr, 2014 02:16
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This would be in 2024, ten years from now. Several year long stints at ISS would have been completed. Also this would be ten years after EFT-1.
The first year-long mission at the ISS isn't planned to start until 2015. However what you appear to be assuming is that any issues that come up in the tests are able to be addressed and retested enough times to ensure that they have been solved. That might happen, but it might not. Depends on what they find, and it depends on how fast the solutions get funded, built, flown up to the ISS and the testing can be done. Lot of "ifs".
This is why assuming we're ready to pull the trigger on an HLV-based human exploration program is premature, since we have not yet figured out what our limits are for humans beyond 6-month stints in LEO.QuoteShould be long enough to have figured the heat shield out.
As of today, with the heatshield that is not capable enough of coming back from locations beyond the Moon, the MPCV is overweight. At a NASA news conference last year (don't remember the date) NASA was asked when the MPCV weight issue would be solved, and NASA said they thought they would be fighting it up till the first crew launch (i.e. EM-2).
No doubt that could be addressed faster if more funding was made available, but then you'd have to throw in the additional funding to change out the heatshield for a more robust one. If a mission was identified that required the MPCV to return from beyond the Moon, I'm sure NASA would be identifying this issue as needing funding, but so far Congress and NASA haven't been discussing funding any missions at all beyond LEO. I'd rank it as a low probability at this point... -
#39 by Coastal Ron on 03 Apr, 2014 02:21
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Good article, stupid mission. Does not capture public imagination...
Does NASA have a requirement to "capture public imagination" with every mission it does? If so, does that mean that NASA is really just a form of government supplied entertainment?
Because if that's true, then I want to be able to vote for missions. And why not! Especially if the whole goal is to capture my imagination, AND they are using MY money to do it.