ARM Defenders Forecast Nasty Things If It Is Cancelled
Saving NASA’s ARM and the Journey to Mars, Op Ed, Louis Friedman, Space News
“The House Appropriations Committee may have just induced such a paralysis by proposing to block funding for NASA’s Asteroid Redirect Mission (ARM). This mission represents the first step in the Journey to Mars, advances needed technologies for Mars and gives Orion and SLS their first real exploration mission. If their action to stop ARM is allowed to stand, there will be no human space exploration earlier than 2030: a delay of at least 5, and more likely 10 years, in any journey to Mars. The space community’s lack of support for NASA and ARM is a shot in our foot. Its political lesson, of undermining a presidential initiative for a human Mars goal, will not be lost. The community’s fractionation, whereby the scientists are happy with their robotic missions, the industry is happy with their rocket contracts, and the technologists are happy with their flight demonstrations, leaves out only the public who would like to see a grander human venture marshalling the talents of all these communities.”
Seeing the end of Obama’s space doctrine, a bipartisan Congress moves in, Ars Technica
“Although the House language must still go to conference with the Senate, it seems unlikely anyone in that body will fight too hard to save the asteroid mission, Capitol Hill sources told Ars. Even if the administration vetoes the bill, it doesn’t really matter to Congress, because key members of Obama’s leadership team, including NASA Administrator Charles Bolden, will probably be gone next year. This year’s legislation effectively lays down a marker for negotiations with the new occupant of the White House in 2017.”
Keith’s note: C’mon Lou: the reason that so many people are against ARM is that its avowed purpose of enabling humans to go to Mars has been repeatedly demonstrated to be bogus – at best a needless detour. Friedman’s own words focus on the case in point: ARM is an attempt to give SLS/Orion somewhere to go – other than Mars. The Planetary Society co-hosted the workshop that spawned this idea and helped lobby the White House to include it as a feel-good thing to do. So their disappointment is understandable. ARM’s total lack of credibility in any reasonable #JourneyToMars scenario is widely accepted by robotic and human exploration communities alike.
The real reason why the Planetary Society supports ARM is that it delays sending humans to Mars. One look at their Humans Orbiting Mars report and you’ll see that they want to take longer to get to Mars and only play around on Phobos when they get there. Their own staff overtly state their reluctance to send humans to the surface.
Friedman’s statement that ARM cancellation would mean that “there will be no human space exploration earlier than 2030” demonstrates a certain level of cluelessness on his part. I guess he missed all of that SLS/Orion-based Deep Space Habitat goodness that was all over the news a month ago.
Lou Friedman wants us all to think that dire consequences will result if ARM is cancelled. I’d suggest the opposite: by focusing NASA’s limited resources on the things that actually get humans to Mars sooner – we will actually get humans to Mars – sooner.
– The Planetary Society Is Against Human Spaceflight, earlier post
– Planetary Society’s Mars Mission Takes Longer To Do Less, earlier post
– NASA’s Boulder Retrieval Mission is Doomed, earlier post
– NASA Advisory Council Wants to Cancel Asteroid Redirect Mission and Send it to Phobos Instead, earlier post
– Asteroid Boulder Retrieval Mission Needs a Precursor Mission, earlier post
– Asteroid Boulder Retrieval Mission Starts To Drift Away, earlier post
There is pretty much a consensus that SLS/Orion will revert to lunar landing as its primary mission. It does make more sense. That still begs the question, however, whether the operating cost of the system will prove competitive and/or sustainable.
The costs will quite simply not be sustainable. That’s the reason Apollo/Saturn funding was slashed years before Apollo 11’s successful lunar landing. It was a folly from the beginning to think that replicating the Apollo/Saturn transportation model (very large expendable manned beyond LEO launch vehicle) would be successful in any way, shape, or form.
That’s OldThink operating where equipment is smashed. It’s a new day.
I’m hoping that SpaceX is encouraged to make a lunar lander out of a Dragon. Would be quicker to evaluate since it only takes a few days to get there versus 9 months to Mars.
That’s not a terribly difficult thing to do, though it will require some modification of the Dragon. Removal of the heat shield, life support systems and other things humans need but a lander doesn’t, like the acceleration couches and the docking system on the nose, and turning the trunk into a fuel tank, that sort of thing.
I would like to see SpaceX make a human capable lunar lander. Would be interesting to see what they would come up with for manned lunar landing and long duration stay on the surface.
They would basically still do what I outlined in my comment. Turn the trunk into a fuel tank and remove the heat shield, though to take off from the Moon again the trunk will need to have landing legs on it.
Even for a Hohmann transfer from a 250 km low-Earth orbit, you’d be coming in at 2.5 km/s. That’s pretty fast. That’s a mass ratio of 2.0 or 2.9 (for a SuperDraco and a Raptor, respectively.)
Copied from a previous post of mine:
Getting from lunar orbit to the lunar surface or from the lunar surface to lunar orbit requires a dV of approximately 1,600 m/s.
Dragon v2 dry weight is 14,100 lb and it carries 400 gallons of fuel, we know this from the FAA’s Environmental Assessment of the Firefly testing program, which gives the dry weight and maximum fuel capacity for the DragonFly test article. This is likely to be somewhat different than the actual Dragon v2, but should be close enough for our purposes. Dragon uses NTO and MMH as oxidizer / fuel for the Draco and SuperDraco systems. 400 gallons capacity gives us a fuel mass of about 4,400 lb.
Running the calculations with these numbers gives us a dV of about 430 m/s on the lunar surface.
Crunching more numbers – to make up the shortfall of 1,200 m/s, Dragon v2 will need about 15,000 lb of fuel to get to lunar orbit from the lunar surface, or an approximate volume of 1,400 gallons of fuel in total, or roughly 1,000 gallons more than it currently has.
Keep in mind, this is a very rough estimate, but
it’s a ballpark figure for what would be needed.
SpaceX’s website gives the trunk’s unpressurized volume at 14 m3, or almost 3,700 gallons.
The trunk could be converted into a fuel tank that is discarded right before landing, and would easily contain enough fuel for the landing.
Fair enough. I did the numbers for a direct landing from the LEO-to-Moon transfer orbit. If I am repeating your calculations correctly, that would take 2035 gallons (for a SuperDraco) out of the 3700 available. That’s much better than I thought.
Now tell me how they are going to take off again.
If they’re going to take off again, that would require landing legs on the trunk.
A question for the real scientists hereabouts: what about the so-called “ballistic capture” method? The idea that the spacecraft approaches Mars at essentially the same speed as Mars’ orbital speed, a technique that according to at least one source has been used by GRAIL to orbit the Moon. It’s slower, and I don’t know how much slower, but it does not require launch windows, and it reduces fuel by roughly 25%:
http://www.scientificameric…
“whether the operating cost of the system will prove competitive and/or sustainable.”
It won’t, because it was never designed to be. That doesn’t preclude doing something with it, though it’s likely it will wind up being a fairly small production run (like the 15 Saturn V rockets that were built).
ARM died the moment Congress forced SLS onto Obama. The whole core of Obama’s 2010 plan was to free up the $3b/yr being burned by Constellation, in order to develop new technologies. The manned asteroid rendezvous was merely the nominal “goal” intended to focus NASA’s tech dev path. BEO payloads, long duration ECLSS, deep space ops, etc.
Once NASA had to tow an asteroid close enough for SLS/Orion to reach, the “goal” became a sad joke, a demonstration of the extraordinary limitations placed on NASA by SLS. (Previously I’ve likened it to towing an iceberg into NY harbour so that Adm Byrd could stomp around on it, shouting “I’M ASPLORING! Derp!”)
No idea why the Administration persisted with it beyond 2010.
It’s sadly true that the ‘towing’ announcement seemed pretty silly in the context of astroid exploration.
But the argument that ‘towing’ killed ARM is hard to understand, at least on one level; when proposed I wondered if the effort would develop perhaps never-needed tech to divert an errant incoming body.
I’d argue it’s not so much the towing that is the issue. The issue is that astronauts wouldn’t be *going* beyond the earth-moon system. We’ve already been to the moon. It’s time to go further out.
in a mere three years we’ll be coming up on the 50th anniversary of the Apollo 11 moon landing. If we can’t go beyond the moon after 50 years, that’s SAD!
As you point out Apollo was unsustainable, so in a sense we have never gone even to the Moon in a way that we can sustain. In fact we are just beginning to learn how to go to LEO in a way we can sustain.
Agreed. This is a good point that the pro-moon supporters make. The pro-Mars supporters counter by saying “been there, done that”. But, if we do go to Mars just to perform half a dozen missions, then stop due to the high costs, have we really accomplished much?
I’m all for developing affordable beyond LEO transportation architectures. Not throwing away billions of dollars in hardware on every mission is the key. Reusable vehicles are certainly required, but the infrastructure to support them starts with LEO fuel depots. If that is later expanded to include mining water from the lunar poles and CO2 from the atmosphere of Mars, so much the better.
“perform half a dozen missions, then stop due to the high costs”
Put it another way, if occasionally do something then it’s a stunt. If doing something routinely then it’s a business.
That’s the gripe I have with the people who complain about scientists not wanting people to set foot on Mars YET.
We have ONE SHOT at Mars, as far as finding life and being sure we didn’t bring it with us. (Or less likely, finding out we accidentally killed it.)
In archeology, it’s common to decide NOT to excavate a site because we hope that in future decades the technology will be there to be able to examine it non-destructively. Excavating a site is ALWAYS destructive. You always lose information, forever.
The Mars prize is not stomping around and planting a flag, nor (as much as I admire Musk’s accomplishments) is it going to be a haven to save us from ourselves.
The Mars prize is knowledge.
There is NO REASON, no rational scientific reason to rush to Mars before we are prepared to do it competently and carefully, both for the protection of the science we can glean and for the protection of people going.
The only reason to rush to Mars is “because I want to see it happen before I die…” which while an understandable emotion (which I share to a large degree) is NOT a good reason.
I’ve said before that too many people see the space program as their “personal fantasy fulfillment machine.” Well, it isn’t. It should not be.
NASA is a science and technology program. Humans should be sent to Mars when it is scientifically and technologically sensible. That may be sooner than some think, but if it’s done in a “get there before 2024” rush, then that’s NOT doing science.
That’s doing self-gratification. There are steps on Mars that have not been taken that need to be taken before human steps are taken.
Unfortunately, it is fundamentally impossible to prove a negative. We will never prove there is no life on Mars (e.g. kilometers below the surface, where it can be found on Earth) or prove that there was not life there at some time in the past.
When I hear people say “not yet” I want to hear their criteria for when. Until we prove there is not and never was life there is exactly the same as saying never. Until we are reasonably sure could be a different matter, but it depends on your definition of “reasonably sure.” Unless you get specific, that criterion could mean anything.
The reference to archeology is interesting (and I’ve heard something about what happened to Schliemann’s Troy.) But what is the criteria archeologists use, when deciding to delay digging until less invasive technology is available? Surely it is not any possibility of doing any damage. They must have some criteria for balancing potential harm against the harm of endless delay. I wonder what those criteria are.
Oh, of course, we can never be sure… but we have to at least have a good strong program of robotic missions specifically designed to look for life before we send people. Not search every inch of Mars… but realistically we haven’t even really TRIED yet. We’ve simply sent some missions to look or areas that suggest that conditions may once have existed where life could theoretically have evolved.
We have only looked macroscopically We need to fund a good suite of
orbiters to look or the best potential landing sites (we need to do that for a manned mission anyway), and then a number of landers that can do some REAL sampling and testing. We haven’t even sent microscopes, haven’t sent anything to try to see if cultures from spots with moisture grow anything, etc.
I’m not talking about waiting ages… but have barely done the prep work. A well-funded 20 year program with launches during every window is the kind of thing I mean.
Frankly, we haven’t really TRIED looking yet. We’ve only sent generalized scouts, essentially. We’ve sent nothing that can look closely and specifically look for and try to confirm biology.
I see a similar situation with METI. The inherent selfishness and childish impatience. Unable to see the difference between “not yet” and “never”. (Something children start learning around 3-4yrs old.)
Let’s say that a few microbes are found on Mars. What then? What is our responsibility to those microbes?
Or maybe there’s some actual multi-cellular life. What then?
I dunno. I’ll let others argue about that. My concern is what we learn by finding those microbes.
You are raising difficult questions about environmental management. I could, for example, point out the harmful effects of goats on the land they are allowed to graze on. Some could argue that other species would be better of if they were extinct. Others would favor preserving them. If there is no clear, obvious answer for terrestrial species, I don’t think there will be a clear, obvious answer when we discover an extraterrestrial one.
{sigh} You really don’t see the utterly unique scientific value in the only non-terrestrial life ever discovered?
No, he just ask, “What then?” That’s a good question. The answer could be anything from keeping them in laboratories/zoos and then doing what ever we like with the planet, to declaring the entire planet off limits to any spacecraft (with or without astronauts) forever. Both extremes would be a poor choice (in my opinion) but they show how broad the range of possibilities are.
What then? sounds like a reasonable question. Mr Spencer did not ask “who cares.”
Indeed. As you say, the question has fairly distinct limits at both ends.
I very much doubt that the presence of microbial unicellular life would dissuade those persistent humans, particularly if the beasties were easily distinguishable (DNA, chirality, or some such). Even primitive multicellular life wouldn’t keep humans off Mars unless it happened to be violently toxic to earthlings. The humans will wring their hands but in the end they will come.
In fact were I life on Mars I’d be afraid. Very afraid.
Well, that’s more specific than anything I’ve heard before. However, the things you say we’ve never tried have been done already. Perhaps not as well as they should be, but…
Orbiters to look for the best potential landing sites: Mars Reconnaissance Orbiter has been returning 0.3 m resolution images for 10 years. It doesn’t operate continuously, and I don’t know what fraction of the surface they’ve covered so far. But about a year of continuous operation would give all of the surface.
Microscopes: The Curiosity rover has a microscope at the end of its mechanical arm. The resolution is 15 microns, and it’s used for mineralogy, not biology. But it’s a microscope so you can’t really say we’ve never sent one to Mars.
Try to see if cultures from spots with moisture grow anything: The Viking landers did try to culture surface samples and nothing grew. Admittedly one experiment gave ambiguous results (interpreted as a false positive due to soil chemistry making the sample fizz when water was added) and the samples weren’t from a particularly promising location.
So, instead of saying we haven’t done any of those things, you should be saying we haven’t done them well enough. I don’t disagree. Now someone needs to decide what “well enough” is, and get people to stick with that decision rather than saying, “still not good enough” in twenty years.
Mars Curiosity does not have a microscope. It has a macro lens. It CANNOT resolve microscopic details. It CANNOT resolve anything too small for the human eye to see.
As for orbiters, I am talking about something orders of magnitude more than what we have sent. The orbiters we ave sent are few, and they are old,
and they have only the capability to give us the most VAGUE idea of where to look for life.
The viking landers did not try to grow cultures in the sense that I mean. They sniffed for reaction gases. A kid at home looking at moldy bread with a $100 microscope is better equipped.
A badly funded inner-city high school science class has more powerful microscopes than have ever been sent to mars. They have better equipment for growing cultures than has ever been sent to mars.
Well, JPL claims that the instrument on Curiosity is a microscope. I have noted that their PR people can be economical with the truth. But 15 micron resolution is way better than _my_ naked eye. That’s less than a thousandth of an inch, if I did the unit conersions correctly. Are you eyes really that good?
The Viking experiments did take samples, add water and nutrients, and look for signs of metabolic activity. Not samples from ideal locations, and not looking for activity in what we would now consider ideal ways. But they did look. This is a case of you saying they never tried the experiment and me saying they did, but didn’t do a great job of it.
As for the remark about inner city schools being able to do a better job of culturing bacteria, spores and other things, you don’t need to limit it to high schools. As a surviver of the Washington D.C. public school system, until I was ten, I can assure you that even the elementary schools are quite capable of growing molds and bacteria. Or to be fair, they were in the 1970s.
But your comments about orbital data are hard for me to understand. You said you would want global coverage and the the necessary resolution would be simar to what would be required for a human landing. I pointed out that MRO had already provided that data. Now you say that this is insufficient.
I’m simply asking what “enough” is. “Better than we have to date” is not an answer, since that is a statement which can be repeated forever. If global imaging at 0.3 m resolution is not enough, would 0.1 m or 0.05 m satisfy you? I want a target measurement requirement, not a vague “until I’m satisfied.”
Would there ever be a reason to “settle” Mars- something far more grand than, say, Antarctic activities– in your view?
I ask in seriousness; aside from the adventure I can’t think of a reason to go to Mars. In fact, I can’t think of a reason for HSF anywhere in space, really, research aside.
Surprising, really, having been a life-long supporter of HSF, and remain so. Objectively it is difficult to support the position except to say that, one day, likely in the far future, the wealth of the asteroids will contribute to habitats housing millions. Speculative, for sure. And I suppose that if that’s our future we start with the first step.
But looking at it from 2016 the tech is woefully inadequate. Not even close to the ships regularly plying the North Atlantic in the 18th century. More like the outriggers used by Micronesian peoples to slowly populate remote islands. And at leas they didn’t sink the boats.
I don’t see any reason, no. I have the same fantasies as we all do, of course. Vacations spelunking Mars caves, etc. But until we somehow rewrite the laws of physics I think more than a scientific outpost at best is not realistic.
I don’t think we need to rewrite the laws of physics. A vacation on Mars is as realistic as flying to Paris in under 12 hours, for the price of a few days’ pay at the minimum wage. It’s just that we needed about a century of engineering work to make the flight to Paris work (at that duration and cost) and we may need another century to do the same for a vacation on Mars. But no physical laws need to be harmed in the process.
But caves on Mars made me remember another tourist opportunity. When I was working in a lab at UC Berkeley, one of the grad students brought in and tacked up a topographic map of Mount Shasta. He was planning on climbing it on his next vacation. The next day, another graduate student (from India or Nepal, I forget which) brought in and put up a topographic map of Mount Everest. The next day, I put up one of the Olympus Escarpment. (8 km, average slope of 45 deg., if memory serves.) They all agreed that it wasn’t impossible, but it would be a technical climb (e.g. requiring gear.)
If we can bring the cost down a bit human spaceflight for research or tourism will make sense.
Decades ago, PopSci did occasional pieces on self-driving cars, imagining magnetic strips embedded in roadways used by the car. The editors never imagined (pointed out down thread) GPS and in the near future detailed static onboard maps of the entire country with sign and building locations- on every production car, maps easily updated just as Mr. Musk happily reaches into my car when he wishes to update or extract data.
The very idea was ludicrous. In fact even in the 1980 comparisons to some future storage device holding the Library of Congress seemed out of reach.
Nowadays the LoC is easily storable on local devices. But the advent of instant access to (nearly) any fact anywhere in the world could not have been imagined.
And so we find ourselves, in the context of the ‘why Mars’ discussion, in the equivalent 1950s when the rocket boys thought they’d be on Mars in 1970, launching from one of many space stations.
The enabling tech we need- the equivalent of GPS, and the internet, and microcomputers and the like- that tech isn’t even visible yet.
I always like thinking about how early science fiction writers never imagined that when the first explorers landed on the Moon, that people back on Earth would be watching it live.
But I also think about the fact that so many of the great achievements and breakthroughs of the past few years are all about electronics. In the end that is just moving electrons and photons around. It’s about moving data and images (huge amounts of it) around very quickly.
Moving mass is a whole different problem, one that compared to electronics has progressed at a snails pace.
Consider the speed improvements for passenger airplanes from 1919 to 1952, from barely 100 mph to over 500 mph in just 33 years. But then we hit a wall, and sixty four years after the debut of the de Havilland Comet we are still travelling at just over 500 mph, with breakthroughs always on the horizon but never getting any closer.
“the rocket boys thought they’d be on Mars in 1970, launching from one of many space stations”
Exactly. Moving mass, especially with humans on board, has been a much tougher nut to crack than anyone imagined.
Commercial aircraft speeds may not be applicable. In that case, going from 100 to 500 mph didn’t require anything fundamentally new (other than jet engines.) It was mostly a matter of making the existing systems better and more efficient. But that’s up to about Mach 0.8. If you want to go faster, it starts getting inefficient (the transsonic regime is a terrible place to fly) and once you want supersonic, there are a whole new set of problems. Some political, from people who don’t want sonic booms and insist want the aircraft to stay subsonic when over land. I’m not sure I see anything equivalent to Mach 1 for planetary spaceflight. Lots of problems, but none that make it easy to improve up to a point and very hard to go further.
For aircraft there is also the problem of heating when you go beyond about Mach 2. Of course that’s not applicable to spacecraft either. But what I was referring to for analogy is that what is needed for practical supersonic flight is more efficient and abundant power. Modern turbofans are incredible but still short of what is needed, after six decades of trying.
Currently in spaceflight we are forced into using trajectories that require the least amount of power. If we had more efficient and abundant power we could accelerate quickly towards our destination in space, and have plenty of power for the tremendous deceleration requirement we have now created by doing so. And plenty of power for rapid acceleration homeward, and massive amounts of power to decelerate as the ship approaches Earth. And not to mention that with plenteous power you can move a lot more mass. My point is that the pace of innovation in electronics is mind boggling, the pace of coming up with abundant and efficient power for moving mass has been much slower in comparison. With of course breakthroughs perpetually on the horizon.
In that case we should be investing money in space technology, as the Obama Administration originally proposed, not launch vehicle construction. No point in planning a mission until we know how we are getting there.
There is one simple reason to go to Mars, it’s not planting a flag, it’s not saving us from ourselves, it’s not even knowledge as such, it is because one day our destiny will be among the stars, life on earth has spent billions of years evolving, should that all one day be for nothing? That would truly in my opinion be the greatest tragedy of all The lives and sacrifices of our parents, grandparents, great grandparents and back generation after generation would have been for nothing. If we look hard enough there will always be an excuse not to go to mars, when do we say we (or Mars) are ready. The fact is we are as ready as we will ever be to start the journey and Mars will just have to be ready too, we could send a million robotic missions, we might find some form of life, we might not, if we found one form of life, do we then say we must send more robotic missions to search for other forms of life before we send humans? You could argue that viewpoint for ever, In the end we just have to make the best decisions we can but in the end we have to move forward. Elon Musk is someone who seems to me to have the right idea, we start now and we push onward trying to make progress, trying our best to do things right, trying to learn from our mistakes but in the end we need to move forward not simply tread water saying it will be for our children or grandchildren to explore space, because for all we know our children and grandchildren may end up saying the exact same thing then a thousand years down the line mankind will essentially be no further forward.
The path to the stars doesn’t pass through Mars.
Mars is a dead end, a hole in space into which you would pour endless money and resources and achieve nothing.
“The path to the stars doesn’t pass through Mars.”
In my opinion it does, at least for the time being, it is a tiny baby step on a very long road, learning how to not only survive but hopefully eventually thrive in a environment very different to our own would not be “achieving nothing”
That’s my point. It’s not on the road. It’s a long and expensive detour down a dead end road that contributes nothing to the journey you want to make.
Well, in the same sense that the route to Mars isn’t through Luna you are correct. There are some very thoughtful people looking at a real road to the stars over at Centauri Dreams.
Destiny?
I don’t disagree with your point at least from some sort of existential point of view. In the context of the capitalist world we find ourselves inhabiting that dog don’t hunt.
“it is because one day our destiny will be among the stars”
This is where the “fantasy” thing comes in.
Even if we manage to achieve half light speed (which we wont), a trip to the nearest star will still take years.
There are BILLIONS of humans on earth. It is possible that at some point in the distant future we might be able to expend huge resources to send a few humans to another star system. Far more resources than their fair share, and in the process further worsening and impoverishing the BILLIONS of humans left here on earth…
…and in the even that we DO manage to send a relative handful, a fraction of a percent of humanity to the stars, the future of the human race will be – ON EARTH. Billions of humans. On Earth.
Here. For good. No matter what. No matter what the movies and TV shows have told you.
Humanity will be an Earth phenomenon that may have a few relatively wispy tendrils reaching outward.
This is the the thing that bugs me most about the “stars are our future” mindset – it’s the extreme of elitism. It envisions the apex of humanity’s technological progress, the output of the planets resources, the goal of humanity itself – as being the abandonment of virtually all of humanity for the sake of the enrichment of a tiny elite.
We are not lifting billions of humans off the earth and sending them elsewhere, so to expect the resources that belong to those billions of humans to be expended to send a lucky few off to escape the mess we make in the PROCESS of exploiting those resources, while leaving the bulk of humanity here to rot… it’s a sick philosophy.
Elitism, huh? Enrichment?
So THAT’S how Armstrong got so rich!
Who knew?
Michael, I think you know what I meant…
Not one person can say what the future will hold, no one knows what will or will not be possible 1 year from now let alone 50, 100, 1000 years from now. Why should we not set our sights as high as possible, traveling to other stars is not a “fantasy” it is an aspiration, a goal albeit a seemingly impossible one. It is NOT leaving the bulk of humanity here to rot any more than Columbus, Da Gama etc left the bulk of Europe to rot it is about expanding horizons. It saddens me how the mere mention of the idea that we should one day aim for the stars seems to bring out the luddite in so many people,
No, no, at least for my part I’m not a luddite. In fact I’m a serious early adopter. But I so appreciate discussing the edge of what’s possible, and I think that there is much to be gained by taking a longer historical perspective.
In truth space will be settled in ways we haven’t yet imagined as we pontificate over keyboards. Remember the TV show called “Connections”?
It is always interesting to consider and discuss the possibilities of what the future of space travel will hold, however I do find there are a number of people (not including yourself!) (often with a very high opinion of there own scientific knowledge) who immediately there is a mere mention of possibilities that go beyond our current limited knowledge of physics will jump in with often very condescending posts that condemn anyone who might consider these interesting possibilities as “fantasists” “sci-fi daydreamers” or “UFO conspiracy fanatics” who do nothing but harm to their beloved “Science”
The truth is as you say Space will be probably be settled in ways we have yet to even imagine, considering these almost infinite possibilities should not be a cause for put downs.
OK. Two questions for your doom. One, what if we don’t exploit the resources here on Earth, What if we do it by mining Asteroids and Mars? Two, is your alternative to simply condemn all those billions you express concern for here on Earth anyway, and have no hope for expanding man outward? Are you saying because everyone can’t go, that no one should? ARM to me always appeared to be a first step in learning to exploit and utilize the hundreds of times more resources that are available in space over what is available on Earth. Being able to exploit mineral deposits not buried at the bottom of a well that is itself at the bottom of the Gravity well we call Earth is how we create wealth and space industry.
I mean that it reduced the concept of ARM to “visiting a (necessarily tiny) piece of rock towed just inside SLS/Orion’s range, but no further.” It reduced ARM to pretence.
I have no objection to a major robotic sample-return mission. ARRM, the robotic side of post-SLS ARM, was the only redeeming feature.
If the object is small enough for ARRM’s robotic tug to divert, it wouldn’t be a threat.
Not necessarily. Just pose the question in a different way. If the ARM robotic component was designed to move a large enough object to be a meaningful destination for the human component, then it would demonstrate technology for diverting an hazardous object. That is not the plan, but, at the earliest stages of the concept, it did look like that might be the plan. So Mr. Spencer could, reasonably, have once hoped that this might be true.
It wasn’t. That’s my point.
Yea. A mistake on my part, never for a moment imagining that they’d divert an asteroid just to make it closer for SLS. I should have been better informed.
ARM died when the rocket and capsule could not do the job *AND* when Congress could not let go of SLS/Orion.
When you design a rocket and capsule for lunar only using decades old hardware, it is no surprise neither can step up to the Space Grand Challenges. Besides the costs of the expendable SLS (solids with crew; no one would launch a 3 mT capsule on a 100mT LV to LEO; …), Orion could not return from an asteroid because CxP selected Apollo’s AVCOAT for its heat shield, even though PICA, launched in 1999, re-entered Earth in 2006 at 12.9 km/sec, the fastest entry ever of a man-made object. The architecture is discouraging at best.
Heading to an asteroid has been part of the plan for DECADES to test out the deep space transportation elements, even if towing was involved, ignored with Apollo redux at the expense of everything else, so perhaps persistence is what it takes to change the path. To an asteroid would not be a detour if it included the proper architectural elements that are geared toward stepping up to the grand challenges.
The technology for a genuine asteroid mission would have been almost all that is required for a Mars-moon mission. (Bit more delta-V, slightly longer duration.)
So Obama says “Go to an asteroid”. Ten years later it happens. Prior to that first asteroid mission, say in the second year of the subsequent President’s first term, s/he says, “Go to Mars! Starting with the moons”. And so, starting just three-to-four years later, there’s a series of missions with astronauts visiting Phobos and Deimos.
And, of course, during that decade, landers are being developed, and suddenly a Mars landing is doable by 2030/31. (Although 2033 is better.)
So in 2018-2020, NASA sends astronauts to an asteroid. A few years later, they send astronauts to Phobos or Deimos. A series of visits later, they send the first Mars surface mission. Meanwhile, SpaceX and co are delivering astronauts to to the ISS, hopefully sparking the commercial-spacestation era.
Even allowing for the usual NASA slippage, how does that timeline not “restore America’s greatness in space” vastly more than SLS?
The simple answer is No..further raise the bar.
NASA’s purpose is to solve problems and step up to the Space Grand Challenges, with the further goal of expansion of the economy. NASA needs a balance of missions and R&D to expand the economy since ‘to Mars’ and beyond requires multiple technologies.
Take solar and nuclear, where both can help the economy and exploration in the short and long term. Missions within decade may be a bridge to far for nuclear, but clearly has some commonality with ARPA-E’s Safe and Secure Module MW Size Nuclear Power effort.
While its true that if the idea is something that would exist after a couple of decades, it can’t be the first thing, significant effort at lower cost can coincide with raising TRLs. IOW: Tech. spinoffs to the economy often do not require missions with TRL 6 to 9 efforts due to differences in space vs earth requirements.
Contrast this with 8B/yr on ISS/SLS/Orion….
No idea why the Administration persisted with it beyond 2010.
Because Congress insisted, and Obama was not willing to invest the political capital to overcome their resistance.
Congress didn’t insist on ARM.
No, but the administration did, and Congress…went along with it.
And the Administration only proposed ARM once it became obvious it was being saddled with SLS, a rocket it did not want. It had to come up with a mission it thought it could afford to use it on, and ARM was it.
Congress insisted the Obama Administration provide a mission for SLS/Orion. Not much that canbe done with a system that cannot go beyond the moon but lacks landers to actually land on the Moon.
Not really. ARM was a produnt of SLS. There was and is no prospect of SLS/Orion enabling a direct human mission to an asteroid. There is, in fact, no use for them that could be pursued witout major budget increases. ARM was invented as a way to provide these investments with a use that could at least be claimed to be reloated to furthering human exploration without making the investments needed to actually further human exploration. In the finset tradion of all pork barrel projects, it was divided up between NASA centers to giive it a presence in as many congressional districts as possible.
It was born out of politics and looks like it will die the same way…
I have heard that NASA quietly changed direction several months ago towards developing a cis-lunar vehicle for moving between earth and moon. It will be based on modified and enhanced ISS modules and systems. This is THE appropriate direction and what they should have started working towards a decade ago. A lot of people, notably Paul Spudis and a small working group he brought together, promoted cis-lunar first back around the time of the last Shuttle flights, five years ago. Opening up cis-lunar space to cost effective manned missions was also the direction that the post Apollo architects chose, in the early 1970s. I’m glad to see the current generation of NASA managers has finally gotten around to moving towards something that makes sense as a next step. .
Interesting, and the evidence to support your statements re: NASA’s ‘quiet’ direction?
Cheers
I don’t have anyplace to send you on the internet, but people who have been involved in the new activity are not sworn to secrecy. They have a task force working on it.
Well there you go. This can only be described as rubbish since if it was true then the blogs such as this one and NSF would be all over it. Rumours wouldn’t play any part in it. Come back when you have something factual.
Cheers
This seems a bit harsh. There are many facts in this world that do not appear in blogs. With all due respect to Keith and NASAWatch excepted, blogs are not exactly known for the high level of their fact-to-noise ratios.
It depends on the nature of the study.
If it’s anything significant, it would probably be reported, or at least mentioned, at some forum like the Mars Exploration Program Assessment Group. That wouldn’t stay quiet for long (and the presentations would go online.)
If it’s two guys doing a concept study because his boss wanted a plan B in his back pocket, I’m not surprised no one heard about it. But then, it would hardly be NASA “quietly changed direction.”
I suspect reality is somewhere in between and the officialness of this is somewhat exaggerated.
I am unaware of any formal change in direction but have heard several managers speak of the possibility of shifting to human flight to the Moon rather than Mars under the next administration.
I think that is consistent with my remark about a manager wanting a “plan B” and paying some people to look into it.
Surely there are people at NASA actively engaged in Plan B. And surely in the case of your own research you have backup plans for certain spacecraft failures, for example?
(After all what the heck do you do during those long cruise years!)
Actually, I sometimes get nervous when I don’t have a plan C. But I usually don’t tell people about them and it isn’t official policy until I have to pull it out of my back pocket. Backup plans are fine things to have, but people sometimes mistake having one for giving up on plan A.
Thanks for your rubbish comment. Its worthless. All we can hope is that after the mismanagement of the last decade that perhaps a change towards a more purposeful strategy is in work.
I agree on the point in regards to the need for this SEP class stage,Kieth may be wrong about the other uses.SEP of this class could preposition large objects around mars and cislunar.And its been suggested that the this class SEP could maneuver the next MRO Mars orbiter
The current administration’s “space doctrine” is little more than talking-head narcissism. NASA needs to “redirect” to meaninful activity and (dare I say) activities that are more generally inspirational. And f.w.i.w. I don’t consider rovers on joysticks to be terribly inspirational, even for the Dora The Explorer generation.
In my perhaps naive opinion, NASA needs to focus on useful technology and meaningful science. The best way to inspire kids is to provide better educational opportunities at lower cost.
Sounds like they’re fear mongering to save their program. Seems like an easy mission for SLS would be a lunar orbiter that controlled several rovers on the moon, perhaps on the far side as well. This could be used to test out concepts for having astronauts in orbit around Mars do the same there. Might not have a lot of scientific value.
Yes, an “Easy Mission” for SLS. A billion or two for the rovers, a billion or two for SLS, a billion or five for the lunar orbiter, and all to control robots that we could just as easily control from Earth. You don’t need to be in space to learn how to tele-operate robots. And the autonomy on the robots that would fly to Mars in 20 or 30 years will make the astronauts a liability, not a help.
Autonomous robots will be great, until they break. Astronauts will still be needed to fix things.
Also, until an autonomous robot has the equivalent of a PhD in geology, chemistry, or engineering, they still won’t be able to match the skill of astronauts on site with those very degrees.
The best solution will be to send both because they compliment each other.
I’m not sure I’m convinced your robot repairman role makes sense for an astronaut. It might be cheaper to send another rover. The cost of sending an astronaut to Mars (amortized over the number of repairs) and supporting him for one mean time between failures would have to be less than the cost of sending a new robot.
I do agree with you about autonomous rover’s being far less able to do scientific field work than a human PhD in the appropriate field. But NASA’s track record in that regard isn’t spectacular. Of twelve astronauts to go to the Moon, only one was a trained field geologist. (No, a brief summer school for test pilots doesn’t count.) The Shuttle and ISS program are not much of an improvement: The astronauts with PhDs are not necessarily assigned tasks relevant to their field of expertise, and I’m not even sure that is a consideration in making the assignments.
Send in the clones! Hint: Lunar movie
Cheers
ISS repairs are dependent on logistical support from Earth. The MERs lasted many times thier anticipated lifetime and Curiosity is still fully functional. Human life support in contrast is both complex and maintenance intensive. The principal cost driver with Curiosity is the fact that we could afford only one rover. A second unit of the same design would be as little as 10% of the cost of the first. Finally, in an age when cars are autonomous at 100 km/hr I do not think we can make the case that humans are needed to drive a rover on Mars at a small fraction of the speed.
Where does that figure come from? I’d be impressed with a 50% unit cost reduction.
Prepared surface, sub-metre GPS guidance, clear line markings.
And computers (and sensors) which would fail inside the first hour in the radiation environment of Mars. Or the first night in the thermal environment.
CubeSats, using off the shelf, commercial electronics, have operated successfully for months in Earth orbit. Some in inclined orbits which regularly bring them in to the radiation belts. Some actually built to measure the radiation belts. Are you seriously claiming that the radiation environment on Mars is thousands of time worse than the Earth’s radiation belts? (One hour versus one month is about 750.)
What he is saying is that computers designed for the terrestrial environment would be unreliable on Mars due to radiation upsets. There are various concepts to provide better computing power in high radiation environments at reasonable cost. The most promising strategy is a redundant-processor architecture in which each logical task is run simultaneously on several cores, sort of like RAID for CPUs. I would like to see more support for low cost radiation tolerant computer development, but this seems to be one of the many space technology efforts that has been descoped due to funding priorities.
I understand, but you can buy 20 krad parts. Not from Best Buy, they cost more, and aren’t as high performance. But you can get them. And even soft ones (call it 1 krad, which is about twice a fatal dose for a person) wouldn’t fry in under an hour.
There are also software solutions. The voting system used on the SpaceX Dragon is one. Cassini’s mass memory is soft and subject to bit-flips and sticky bits. The former is dealt with through fairly vigorous EDAC (error detection and correction) and the later by memory management (although the recorder’s capacity goes down a little every time, it hasn’t been necessary very often. Once or twice, if memory serves.)
I don’t suppose you know what sort of laptops astronauts use on ISS. I assume it doesn’t matter much, since the environment is safe for people, the laptop should be fine. But I wonder if they have problems with SEUs.
I’ve used a thinkpad which was in orbit. I agree that rad-hard components are available but as long as the technology is differfent from the mainstream they will lar further and further behind. The redundancy approach might use a different architecture but if the technology is the same they should have a better chance of keeping up with the perfomance of ground-based systems.
Which Daniel wasn’t talking about. Nor was it what I was replying to.
“Finally, in an age when cars are autonomous at 100 km/hr”
He was referring to the systems used in cutting edge self-driving cars. (I presume actually a reference to Telsa’s lane-following.) Those are not using high-end milspec parts nor extremely low end specialist electronics. And they wouldn’t survive on Mars.
They couldn’t find the lane marking, either.
Do you have a source for that?
Because, given the issues that have occurred with radiation messing with deep space electronics, you’re basically saying that dense-circuit consumer electronics somehow has superior radiation protection to specifically rad-hardened milspec gear used to date.
Well, I was thinking of CSSWE, http://lasp.colorado.edu/ho…, but thats hardly unique. Lots of CubeSats operate for months with commercial electronics.
I’ll also note that the SpaceX Dragon does not use radiation hard electronics. It uses several CPUs, running in parallel and checking each other. That’s tolerant of single event errors and commercial components can survive a dose up to 20 krad. (admittedly, not the smallest/fastest.)
I think you’re overstating the difficulties. I’ve been working on Cassini for 16 years. It’s been in relatively high radiation environment much of the time (but not horribly so.) The electronics are mostly 100-krad parts, and sensitivity to single event upsets should (at least roughly) scale. We’ve had no fatal (loss of subsystem) failures from radiation, and the SEUs, bad (latched) memory locations, etc. cause a minor annoyance a few times a year.
For really soft parts (1 krad), I’d expect that sort of thing about 100 times more often. That’s implies no fatal problems in a couple months and SEUs and glitches on a daily basis. And, as I said, 20 krad commercial parts are available. I’m just not seeing the “fail inside the first hour” sort of problem you claim.
“uses a 16-bit microcontroller (MCU), […] at eight megahertz and has eight kilobytes of (RAM)”
Mmmm, cutting edge.
Again, I was responding to someone talking about the kind of systems installed in the Telsa for self-driving.
I was not saying that you can’t buy some kind of low-powered electronics (that were outdated in the ’80s) off the shelf which are intended to be used in space.
In fact, that was my whole damn point to Daniel. Space systems do not run the kind of electronics that are required for high-end autonomy that we see on Earth.
There’s a tendency to look at the state-of-the-art on Earth and say “We can do that in space!” No, we can’t. Those systems won’t work in space. Too much radiation, too much thermal cycling, not enough power.
The MSP430 is a pretty modern chip, and it was not developed with spaceflight or radiation tolerance in mind. Yes, 16-bits, 8 MHz and 8 kbytes isn’t much. But this thing does that on a 1 cm x 1 cm chip, for under a milliwatt. That’s not something they could do in 1980. It’s the same things that make modern microchips small and low power, which also make them more radiation sensitive. And this one didn’t fry after an hour in space.
I’m not saying the most advanced microchips are viable for space applications. Not even close. I’m saying they would probably last for days or maybe weeks (which is inadequate) and the “one hour” remark was a massive exaggeration.
Can you estimate the cost and size for a radiation tolerant spacecraft computer comparable in speed and capacity to a modern terrestrial design, say a home system you could assemble for ~$1000 with up-to-date components from Newegg?
I realize you can do a lot with the systems that are out there. But management has suggested that NASA doesn’t need to invest in AI because they plan to leverage terrestrial AI tech for use in space. Similar software will require comparable hardware performance.
That might be an interesting calculation. But I’m not sure I could do exactly what you suggest. I can probably find the cost and specifications of a flight computer, either currently in development or recently launched. Then we could check the cost of a comparable, home system. I’d have to limit it to a general-purpose flight computer, not firmware burned into FPGAs. You also might want the production cost, not the development cost. That’s harder, since flight electronics tends to be custom. I might have the numbers in my office, but I’m out of town and will be for the rest of the month.
In any case, I do agree flight electronics seems to be on a diverging branch from commercial hardware. Not only in terms of the technology of the chips, but also the applications. It’s a big leap from anything we currently use (which isn’t when you come down to it, all that complicated) to serious AI applications.
Some discussion of the SpaceX strategy:
http://aviationweek.com/blo… Apparently they intend to stay with commercial hardware and try to accomodate radiation by architectural redundancy at the system level even for BEO missions. That may be the only way to keep up with the advancing state of the art.
I can personally attest that a certain electric automobile is nearly autonomous at speeds a good deal higher than 100 km/hr…and a hell of a lot of fun, too.
The Mars 2020 rover is supposed to be the same design as Curiosity, but with a different set of instruments. If memory serves, the cost is estimated to be $1.8 billion, which is closer to 70% than 10% of Curiosity’s cost. Nor is a large fraction of the money going to new instrument development. You can make a case for low cost rover’s, and for reducing costs by reflying the same design. But Curiosity and Mars 2020 do not make the best poter children.
Nor is Curiosity still fully functional. Unexpectedly high wear on the wheels has caused them to drive more cautiously than they planned to, or originally did. It still works, but _fully_ functional isn’t quite right.
The cost of the program is whatever is required to support the program personnel over the program duration. Mars 2020 is a major program with major costs. In contrast the MER A and B were built at the same time and to the same design, and appear to have cost a lot less than twice the cost that would have been incurred if only one had been built and launched.
If we want robotic exploration to succeed, the first think we have to do is to really _want_ to accomplish more per dollar spent in the overall program and plan accordingly. In the case of Mars 2020 I would have suggested building two (or more) identical probes and landing them at different locations, a strategy that has worked pretty well since Viking.
Considering how long it takes to get a new rover to Mars, just sending a new one is not as easy, or as quick, to do as it is to say. Unless you want your next rover to fail in the same way, you need to improve the design. Plus you have to add in how long it takes to wait for the next Mars “window”, which is determined by orbital dynamics and is about every 26 months. So, your “just send a new rover” could take up to three years.
The alternative is to send an astronaut on an EVA and fix the thing and you can resume operations. Even if this takes a few days, that’s still two orders of magnitude faster than “just send a new one”.
As far as not picking the right astronauts for the right jobs, that’s partly a cultural problem with NASA and partly a problem with launch costs (size of crews). It’s been getting somewhat better, but change is taking decades.
Lowering launch costs can increase the size of the crews on missions. One of the problems with ISS is that much time is spent doing maintenance. Commercial Crew will allow NASA to add an astronaut to ISS which should allow more experiments to get done. Arguably, this added astronaut should be a researcher, not a “generalist” who also knows how to fix ISS when it breaks. Time will tell how NASA chooses to fill that extra slot.
I think a private company like SpaceX could make many Mars rovers fairly cheaply. The more ideal solution would be to send humans to Mars which SpaceX may make more attainable, but it will still be a while before that happens. I’m of the view of using the closer moon to try out things before going to Mars.
Except that much of what can be done on the moon won’t be directly transferable to Mars. Landing is different due to gravity and atmosphere differences. In-situ fuel production will almost surely need to be different due to what raw materials are readily available. The water sublimation spacesuit cooling used on the moon doesn’t work at all on Mars due to the thin atmosphere. A Mars suit also has to be much lighter than a lunar suit due to the higher gravity. The dust is different (lunar dust is terribly abrasive due to lack of water or wind to round off sharp edges and corners). The day and night cycle is completely different between the two, which makes the thermal variations different as well as solar power availability different (you need huge power storage capacity on the moon if you’re going to use solar for power).
So what exactly would be done on the moon that directly applies to Mars?
As you say, sublimation cooling for a spacesuit will work on the Moon but not on Mars. But for any long-term operations, it’s not a good idea on the Moon. I once totaled up the logistical costs of the current suit technology and it’s unsustainable. I think I presented that at the last Case for Mars conference (which was about 20 years ago.) The same logic applies to the Moon. The water’s just to valuable to waste. (Well, I don’t know of a good way to eliminate this, but I know how to minimize it on Mars.)
I think you’re overestimating the cost of a rover. The two MER rovers (together) were $820 million, so it’s under half a billion per, not several billion.
It might be cost effective for an astronaut to spend a week or so per year fixing unmanned landers or rovers, and other useful work the rest of the time.
By the way, how is the astronaut going to get to the rover’s location? Cars rarely break down right next to the repair shop.
If the rovers are in the vicinity of the manned habitation, a manned rover. Again, it may take years to send a replacement from earth, so if a broken rover sits on a list of “things to do” until it’s convenient to get over to its location to repair it, so what?
I’m just leery of the “just send unmanned vehicles, never send people” philosophy. Because if we’re never planning on sending people to Mars, then what’s the point of exploring it with rovers in the first place?
As an historic example, the absolutely huge push to send unmanned probes to the moon was in preparation for the first manned landing. It was pretty amazing how many orbiters, crashers, and landers were sent in such a short period of time, which sounds an awful lot like what some people advocate for Mars exploration instead of sending people. But, after Apollo, there was a noticeable lack of *any* US moon probes for *decades* even though the missions which were eventually flown afterwards weren’t expensive at all (relatively speaking). That hints at how hard it can be to obtain funding for even “cheap” unmanned probes.
Of twelve astronauts to go to the Moon, only one was a trained field geologist. (No, a brief summer school for test pilots doesn’t count.)
In all fairness, the geological training that the other five astronauts who flew on J class Apollo missions (Apollos 15, 16, and 17) besides Harrison Schmidt amounted to something more than a brief summer school. NASA estimated that they received the equivalent of a Master’s degree in geology – still not a Harrison Schmidt, but not nothing, either. Given the constraints they had to operate under, the J class missions did some very solid geological surveying.
Of course, I would NOT want to use Apollo as the model for any further manned scientific exploration (or for that matter, anything else) of the Moon or Mars in the future.
I was probably a little harsh on the Apollo geology training. And their instructors were really world-class experts.
But getting a Master’s in geology is a good, solid two-year, full-time job. And it’s proceeded by four years (probably compressible) getting a bachelor’s in some related field. I suspect NASA’s estimate was a bit exaggerated. (Or meant they knew as much about collecting samples on the Moon as the average geology MS of that period. Which is to say, not much.)
I would just say – and Schmidt and Lee Silver seemed to agree – that judging by the results, the J class crews did a pretty good job as field observers. No question the science community would like to have had professional geologists on every mission, but – the results paid off with the test pilots.
Of course, these were only three day missions with very limited equipment; the training could be pretty focused as a result. If they had been sent on 90 or 180 day missions, they would have reached the limits of their training more readily.
Which is the problem with Apollo. It really was “flags and footprints.” And once they had the flags and footprints, NASA decided to cram as much science into the missions using the remaining hardware. And in that regard, they did a pretty good job. But the program wasn’t designed for bringing back science (though follow on Apollo Applications missions would have, to a much greater degree). It’s hard to say that robotic missions wouldn’t haven’t been a much more cost effective way to explore the Moon at that time; more so, now, even with the greater capability to bring along professional scientists on an likely future exploration missions.
I would just say – and Schmidt and Lee Silver seemed to agree – that judging by the results, the J class crews did a pretty good job as field observers. No question the science community would like to have had professional geologists on every mission, but – the results paid off with the test pilots.
Of course, these were only three day missions with very limited equipment; the training could be pretty focused as a result. If they had been sent on 90 or 180 day missions, they would have reached the limits of their training more readily.
Which is the problem with Apollo. It really was “flags and footprints.” And once they had the flags and footprints, NASA decided to cram as much science into the missions using the remaining hardware. And in that regard, they did a pretty good job. But the program wasn’t designed for bringing back science (though follow on Apollo Applications missions would have, to a much greater degree). It’s hard to say that robotic missions wouldn’t haven’t been a much more cost effective way to explore the Moon at that time; more so, now, even with the greater capability to bring along professional scientists on an likely future exploration missions.
I think a company like SpaceX could make many lunar rovers for less than a billion. It sounds like you don’t support the proposed control of Mars rovers from Mars orbit then. Not saying I do, but this would be a way to evaluate the concept.
Tests on Earth have shown that the radio lag between Earth and moon is short enough to allow direct control of a rover. (And indeed, that’s what the Russians did with their Lunokhod rovers in the early ’70s. A farside mission would merely require a small relay satellite in EML2.
A manned facility in lunar orbit would actually be worse, since it could only control the rover(s) while it is overhead. A manned facility at a Lagrange point would allow permanent operation, but be limited to line-of-sight.
But, importantly, Earth-based control would allow round-the-clock operation of as many rovers as you can afford to launch. A manned cis-Lunar facility would be limited to however many astronauts are at the facility. Orion is limited to four astronauts; and if they have EVA spacesuits, Orion is limited to just two astronauts. By definition a cis-Lunar facility would be vastly smaller than ISS, which is limited to six crew. ISS astronauts spend most of their time maintaining the space-station; the cis-Lunar crew would likewise have significant maintenance tasks on top of their rover-control jobs.
And speaking of “as many rovers as you can afford to launch”, there’s the cost.
SLS costs upwards of $2-3 billion per launch. And every crew change would require a full SLS launch. A cis-Lunar space-station (even a small one) would cost upwards of $5 billion. I’d be surprised if you could do the mission for less than $30 billion per decade.
That’s a hideously expensive rover. (And that doesn’t include the cost of the actual rover anyway!)
Assuming a good lunar rover costs $2 billion, including non-SLS launch costs, the cost of your proposed manned teleop team would instead allow fifteen Earth-controlled rovers over the same ten years. And it’s likely that if you’re developing 15 similar rovers in ten years, the per-unit cost would drop rapidly. With rovers to spare, the program managers would also be willing to risk visiting more dangerous sites (such as dropping into “skylights”, or shadowed craters) delivering vastly more science.
That’s a lunar science program.
As I mentioned, this would be to evaluate the concept of controlling Mars rovers from Mars orbit. Also, rovers on the moon can’t be controlled on the far side. That would require orbiters for communication.
A minimum of $10b to do something you could simulate on Earth?
Which is probably why I said “A farside mission would merely require a small relay satellite in EML2” in the very first paragraph.
Which is exactly what the Chinese plan to do with Chang’e 4. It’s supposed to land a rover, similar to Chang’e 3’s Yutu, on the lunar farside, with a communications satellite in a L2 halo orbit. This is scheduled for 2018.
Simulating on Earth isn’t the same as doing it in space. Doing science on the moon couldn’t be simulated either.
A single satellite would only work part of the time when it was in range of both the Earth and the rover. A L2 halo orbit satellite would induce even longer delay times. The whole point of this concept was to try out things days away in lunar orbit that you want to do months away in Mars orbit.
If simulation always works, then why do the US and Russia have problems with their LEO Oxygen and water systems?
You know all the rovers we’ve sent to Mars. You know how they test those? Guess. (Hint: It ain’t by sending them to the moon.)
You want to practice RC’ing a Mars-bot, you can do that on Earth. You will do that on Earth.
Where as an orbiting space-station can magically hover 20 feet overhead?
Which you can’t do because a lunar rover will operate differently than a Mars rover. So all you’re practising is “remotely controlling a rover on unimproved ground”, which you can do on Earth.
You’re proposing spending billions of dollars to practise driving a robot.
Because somehow doing it lunar orbit is somehow magically going to teach us about a mission to Mars.
Purely FWIW, my current preferred ‘Moon First’ mission concept is a ‘road train’ multi-segment heavy pressurised rover that would carry a 2-4 crew expedition on a 28-day trip across the lunar surface carrying out in-depth survey (human and using the rover’s on-board sensors) along the way. It would regularly meet up with resupply landers and, at the end of its trip, meet up with the crew return vehicle, flown out by their replacements. The rover would be a mobile habitat and processing lab and would also have a ‘flat-bed’ cargo carrier to carry supplies and surface experiment packages to be placed at regular intervals.
I’m thinking that we’d be looking at maybe four launches to get the rover, its crew and the first tranche of supplies on the lunar surface with a launch every 14-28 days to back it up. The cargo flights wouldn’t have to be SLS; a Falcon Heavy launching a ‘Lunar Dragon’ would be enough. The SLS would only be needed for crew rotation.
Risky? Certainly; far, far more risky than a short excursion or a stay at a fixed base but, I would argue, far more scientifically productive and it would also probably be perceived in a more positive light by the general public. I think that it would be easier to sell the considerable expense on the grounds that NASA really would be exploring the Moon in an in-depth manner.
To keep the radiation exposure levels of the 28 day mission below current lifetime radiation limits, you’d need around half a metre of solid radiation shielding around the vehicles. Plus a more deeply shielded “storm shelter”.
Assuming 3m diameter cylindrical pressure vessels, that’s about 5-10 tonnes of shielding per metre of length.
So a full lunar night as well? You’d need a nuclear reactor on your road-train.
If you have the ability to put a Dragon on the lunar surface (for supplies) using only FH, then you have the ability to land a crew and a return vehicle. You’d need two or three FH launches and EOR, but that’s vastly cheaper than doing anything with SLS.
I’m not sure where you are getting your numbers. Most studies for Mars missions don’t suggest half a meter of shielding (except, perhaps, in a storm shelter, which could be “crawl under the rover” on the surface.) and that’s for 18 months of exposure, not one.
Moon, not Mars. And the numbers come from NASA’s radiation rules. (I’m assuming each crew will spend time doing EVAs, not just motoring from rendezvous-A to rendezvous-B. Which means the rad exposure in the vehicles needs to be at least RP5 or 10 in order to keep the total mission exposure below life-time levels. (EVA suits are RP0.1, basically non-existent.))
The radiation exposure on the surface of Mars is about a third that of the moon. But even then, most Mars studies are apparently considered naive by the bio/medical side of NASA for exactly that reason, more realistic missions are expected to need to minimise the time in rovers (unless they’re heavily shielded) and especially EVAs.
Let me try that again. The radiation dose for a Mars mission is primarily from the nine months in interplanetary space getting there and the nine months coming back. The galactic cosmic ray flux is the same for the Moon and interplanetary space. The solar energetic particle flux on a trip to Mars between 50% and 100% that at the Moon, due to greater distance from the Sun. On the lunar surface you have plenty of shielding in one hemisphere. So the dose rate is cut in half. Therefore, the lunar surface is, in terms of radiation, similar to interplanetary space on a trip to Mars.
Studies of that, assuming on shielding beyond the usual spacecraft structure and a “storm shelter” typically predict a career dose from the 18 months in interplanetary space.
Now you are claiming someone on the Moon, a similar environment in terms of radiation, would hit the career limit in under a month. I don’t see how those numbers add up. What is your source?
Studies which are considered naive by NASA’s own internal medical people.
That’s not exactly what you imply. Calculating the flux and total dose is fairly straightforward and I don’t think there are any disagreements about that. The problem is that most of the dose comes from energetic heavy ions. We don’t know very much about the medical effects of them. Absorbed, ionizing energy (dose in rad) has to be scaled to measure the medical effects. Now you get into the problem people disagree about. Should you use a best estimate or a worst-case estimate? I believe that’s the issue you’re talking about.