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Asteroid Missions May Replace Lunar Base Plans
An anonymous reader alerts us to a story about efforts to modify the United States' space exploration plans to focus on asteroid missions rather than a lunar base. Scientists, astronauts, and former NASA division directors will be meeting next month to develop an alternative to the Bush administration's Vision for Space Exploration. We have previously discussed the possibility of a manned asteroid mission. Quoting:
"Numerous planetary managers told Aviation Week & Space Technology they now fear a manned Moon base and even shorter sorties to the Moon will bog down the space program for decades and inhibit, rather than facilitate, manned Mars operations--the ultimate goal of both the Bush and alternative visions. The first lunar sortie would be flown by about 2020 under the Bush plan. If alternative-vision planners have their way, the mission could instead be flown to an asteroid in about 2025."
Just because he was an unpopular president everything he did is wrong, and needs to be reverted, once he leaves... Come on get realistic Presidents are people like you and me they make mistakes sometimes huge ones but they are not wrong all the time... I would like to see more work on the moon vs. asteroids. Asteroids seem much riskier without the benefit yet. The moon on the other hand is fairly stable and we could really work out the kinks in exportation.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
If true, this is very good news. Asteroids, the smaller and more numerous ones being undifferentiated bodies, have considerably more scientific value than the moon. It's actually much easier to rendezvous with and return from many asteroids than to land softly on the moon and return. The moon is relatively large, with a big gravity well, and without an atmosphere, aerobraking is impossible. Landing from lunar orbit and takeoff to orbit each require delta Vs greater than 2000 m/sec. Entering and leaving lunar orbit takes even more. Asteroids require earth escape, but that is only slightly more than reaching the moon's high altitude (400,000 km). The velocity change required to rendezvous with the asteroid could be minimized by careful choice of asteroid and launch window.
Asteroids would take much more time to reach, and a mission could not be quickly aborted in an emergency. The communications lag would also be significant; real time conversations would be impossible and communications might even be blocked entirely by solar conjunction for a few days at a time. These are challenges for human space flight, but not insurmountable ones.
Manned asteroid missions have little if anything to do with asteroid deflection strategies. If you want to keep the Earth safe from big nasty dinosaur-killers, you spend money on tracking every Earth crossing Asteroid in the sky, not on sending people to 1 or 2 of them. Early detection of potential dangers makes any deflection strategy (almost certainly unmanned, despite what your favourite movies might tell you) more plausible
The purpose of visiting asteroids is looking for something to mine or doing science to investigate the origins of the solar system.
If we can put a man on the moon, why can't we shoot people for Apollo-related non-sequiturs?
Its fairly logical to think that if its so expensive to get stuff into space, just build it there. While manned missions to the moon and on to mars would certainly be amazing, I fail to see the point of a manned mission to an asteroid. Just send a probe and play around with altering a small asteroid's orbit and bring it into a lunar orbit. Creating an automated system that collects small asteroids (small enough that they'd burn up in atmosphere) and bring them to the moon to be processed would be a tremendous step forward in human expansion into space. Unfortunately, I don't think anything like this would happen until commercial space missions start making it further out there.
For anyone that hasn't heard of him, I'd strongly recommend you check out Bill Stone's TED talk. The whole thing is pretty cool, but its the last chapter in the video thats really amazing.
Given how there was no funding to begin with, it is hard to see how it can be cut back. However, the resulting confusion is indeed highly likely to get rid of both missions at the same time.
Why is there no scientific value in sending people to the moon? Its not like NASA explored the whole thing in the 1960s. We don't know much at all about the levels of water and helium-3 in the surface, both of which are important. Furthermore, seeing as the Earth and Moon seemed to have formed at the same time, investigating the moon can tell us more about the Earth. There is loads more to learn.
If we can put a man on the moon, why can't we shoot people for Apollo-related non-sequiturs?
The only problem with an unmanned asteroid mission is that it may require some human decision from time to time - but normally there is no problem with time delays there. Not much that's in a hurry on an asteroid unless it's heading for Earth. Just put the robot to sleep for a while and recharge the batteries. Keep in mind that there may have to be different robots there compared to the robots we have on Mars.
The thing that's more interesting with a permanent moon-base is that there is a possibility that a lot of the material found on the moon can be used as construction material. It will require a processing plant - and it can't be used for everything, but it's there. Much of the soil is composed from oxides - which means that you can extract oxygen. Allocation of area for growth is no big problem either. The catch is that all this may have a high cost. But what is the cost when the Chinese decides that it's their turn to go to the moon?
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Good, I hope that they succeed in changing that strategy. For any colony to actually be useful and self-sustaining, there has to be some hope of an economic return on investment. The driest deserts and coldest tundras here on Earth are like tropical paradises compared with anything outside our planet, whether that's the moon, Mars, or a space station floating around the asteroid belts. Any space colony would be heavily dependent upon imports for survival (e.g., food, clothing, natural resources, manufactured goods, etc.). That will require a roughly equal amount of exports to balance trade, probably in the forms of valuable minerals and manufactured goods that are best made in microgravity environments. That becomes rather difficult to accomplish if you're stuck in a gravity well like a planet or relatively large moon, because lifting those items back out would be prohibitively expensive. We need to stop obsessing over planets and moons, just because we happen to be bipedal and live on a planet now. Asteroids are the way to go.
Because we can send robots there for half the cost, and the space saved in fuel, life support, and whatnot will allow them to carry much more in the way of instrumentation and tools.
Don't you think that the far longer distance to the asteroids make the overhead of a human presence on the trip there somewhat bigger, compared to a trip to the moon? A continuous presence on the moon would be realistic before 2030, reusing the same equipment with different crews. I fail to see that on the asteroids. Heck, for the moon it would even be possible to get down to Earth in a somewhat conceivable manner in a medical emergency, not so in the asteroid belt. (Ok, we can choose to land on one that passes nearby, but then it's a very limited time window anyway. It's a series of short excursions, not a permanent project.)
All these people seem to think that getting to Mars is the ultimate goal, that gathering scientific data is the point, and we've been to the moon already. This is starry eyed gee-whiz thinking. The quote at the end of TFA explains the REAL goal - we need a permanent colony somewhere other than here. Yes the Moon is a harsher environment, but the cost in time and money to put a colony on Mars is so much higher than putting one on the Moon that it just doesn't make sense. Sure, while we're there we should do some science, but getting people to live there will produce more sustained value than dozens of brief scientific visits to places with only scientific interest. Look at how they consider the Moon now - if a place is only worth visiting a couple of times at most, we're going to run out of places to go pretty quick. A colony would provide LOTS of incentive for private company participation. Building an Earth/Moon ferry service is feasible in 50 years - no private company is going to invest in one to Mars anytime soon.
I want a Moonbase!
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In the book, "The Case for Mars" the author, also the creator of the Mars Direct Plan, argues skipping the moon all-together and go straight to Mars. This is because Mars is full of resources that could be used to make a self sustaining colony, whereas a Lunar base requires everything to come from Earth. Differences between a Lunar Base and the ISS? The Lunar base is on the Moon, and on the Moon you can do geology and astronomy particularly well; on ISS, there's not much useful science.
I'm not sure cruising to asteroids is the answer, but at least there are probably lots of interesting and diverse resources, and the missions could be made lightweight(no lander required). The geology of Asteroids is probably alot different than the Moon's because there was no volcanic past or differentiation. But my opinion is, cut to the chase, go to Mars, its the most interesting thing out there.
It is not just NASA that wants the moon.
I prefer the "u" in honour as it seems to be missing these days.
One big advantage of a crewed mission to a near-earth asteroid over a crewed mission to Mars is that we simply don't have the technology to get to Mars. A transfer orbit to Mars takes 1.4 years (total round-trip time). (This is simply the period of a body in a Keplerian orbit that's tangent to the Earth's orbit at perihelion and tangent to Mars's orbit at aphelion. A spaceship isn't like a car, which takes less time to get there if you drive faster. A spaceship only thrusts with its engines in order to change its orbit.) The big unsolved scientific and engineering problem is how to keep a crew of human beings from getting exposed to unacceptable doses of radiation when they're in Earth-Mars orbital space for that long. The radiation intensity from galactic cosmic rays is much, much higher out there than it is in Earth orbit. Feasible amounts of shielding actually make the problem worse rather than better, because of secondary radiation. According to this article, the duration of a mission to a near-earth asteroid could be 60-90 days, so it avoids this very tough, unsolved problem. There are many other aspects of a near-earth asteroid mission that are also a heck of a lot easier than a Mars mission. You don't have to land in a deep gravity well and then take off again, for one thing. If you look at the history of uncrewed Mars missions, it's pretty damn scary -- the success rate is very low, and that's for missions that don't have to take off and return to Earth, and don't have to provide life support.
The big question in my mind is what is the rational justification for government-funded crewed spaceflight at this point. There's no scientific justification; uncrewed probes give more bang for the buck. The shuttle's only mission is to go to the ISS, and the ISS's only mission is to give the shuttle somewhere to go. Thirty or forty years ago, this was all basically cold war propaganda stuff. It seems to me that the U.S. is having a hard time dealing with an unanticipated outbreak of peace. The rational thing to do would have been to continue harvesting the peace dividend, start ramping down our foreign military commitments, and let both crewed and uncrewed space exploration make the transition to the private sector. Instead we've been blundering around like idiots with our ridiculously large military, and in terms of space exploration we've been choking the scientifically productive uncrewed program by diverting the available money into extremely expensive projects like the ISS that have no rational justification.
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There are numerous alternative architectures that can deliver the hundreds of tons of supplies you need on the lunar surface within practical budgets. But they involve direct commercial and industry involvement. Until these players are fully engaged we will not be going back to the moon in a meaningful way. Most importantly these architectures provide the foundations for going to Mars in a meaningful way. Anyone who thinks you are gonna do anything meaningful on Mars with a handful of crew is simply wrong. It requires a bare-bones crew of at least 90 to support three science teams of 6 each. If you want confirmation look at Antarctic operations to get yourself calibrated. Furthermore on any real Mars mission at least part of the crew that goes does not come back on the first return opportunity. They are there for at least two cycles and transfer tasks and responsibilities to the second cycle crew etc etc. It is getting used to not coming back for 5 years that is perhaps one of the most important psychological barriers we must cross. The moon is a good place to start this- staying there permanently creates an enormous improvement in efficiency. You can finally forget about the retreat to Earth as the only safe option. Worth nearly 3000 m/sec delta V.
So the moon is worthy goal- but it is the practice of developing self-sustaining colonies that is the real barrier.
The Moon-Mars plan is referred to as the "Vision for Space Exploration."
What exactly is the vision? The founding document [large PDF warning] for the "VSE" lists goals and strategies, but no vision of what the goals and strategies are meant to accomplish. A vision involving the Moon could be "create a new civilization on the Moon that might do for the U.S. what the New World colonies did for the Old World." (you can snicker but that is an example).
"Go to the Moon and Mars" is not a vision. It's an strategy.
"Build launchers and spacecraft based on current infrastructure & technology" is an implementation of that strategy.
Again... what is the vision?
Oh, we still dream. It's just that we've replaced aspirations with fantasies.
As an Apollo-era teenager I share my age group's frustrations that I don't have my jet car on Mars yet. Heck, we quit following the last few missions. Been there, done that. But all this smacks of back seat desperation. _IF_ by now we had created a huge space station that had learned to be self-sustaining with zero resupply/repair ferries for years, then it _might_ be reasonable to talk about multi-year manned missions around the inner solar system. But as it is, it's more than a little ugly. Sure, you'd get enough volunteers. But watching them die 30 million miles from earth because something and its backup broke is PR that would set your gamble back many years.
Been to the moon so why bother to go back? Why do we have a permanent presence in antarctica -- the favorable corn-growing season?
And, sadly, I also wonder whether this is likely to be some weird propaganda that costs nothing during any particular year of a presidency but keeps the Star Trek voter happy.