Back to the moon

There's been quite a lot of buzz recently, at least in the appropriate circles, about the future direction of the US manned spaceflight program. At the core of this has been Obama's decision to cancel NASA's Constellation program, initiated under Bush and which would have seen a manned return to the moon in the near future, as a pre-cursor to a manned mission to Mars, and replace it with a different program which is focused on developing new technology to support these kinds of activities further down the road, with a manned asteroid landing planned for the more immediate future. Reactions to Obama's change of direction have been mixed, even amongst Apollo astronauts: Neil Armstrong, Jim Lovell and Eugene Cernan are opposed to the change and consider the cancellation of a near-future return to the moon a bad thing, while Buzz Aldrin has been extremely supportive of the change, suggesting that going back to the moon is a complete waste of time and pushing heavily for a mission to Mars.

The two directions for NASA are multidimensional, and I think it's simplistic to simply take a side. I'm disappointed to see Constellation cancelled, although certainly there were things about it I thought could be better: the DIRECT group's Jupiter rocket family seems like a better idea to me than NASA's Ares family, for example. I think the Obama plan's focus on privatising the development of launch vehicles makes sense, and stayed up quite late to watch the recent inaugural flight of SpaceX's Falcon 9, but I wonder about its suitability for manned flight out of Low Earth Orbit: SpaceX have a direct commercial incentive to develop the Dragon capsule and rockets for launching it - ISS ferry missions - but do they have the incentive or knowledge base for something like a Mars mission? I'm excited about the Obama plan's push for research on exciting new technology like inflatable spacecraft modules and orbital propellant deposits, but I don't see why we can't combine that sort of research with, well, actually going to places and doing stuff. But I think perhaps the central question in this whole thing, the one which is most important for the long-term future of manned spaceflight, and the one where I am the most baffled by one side of the two camps, is the question of whether we should ever go back to the moon, or simply proclaim "been there, done that!" and head straight for Mars.

I absolutely do not understand the attitude of "we've already been to the moon, why go back?". Not only does it not make a lot of sense, it also seems to be an attitude reserved singularly for the moon. Did anybody seriously break this argument out after the first time we reached the north or south pole, or the first time we climbed Mount Everest, or each time we discovered a new island? Of course they didn't. It's really just a silly argument, and so it's disappointing that it's one of the most commonly cited arguments against a return to the moon: probably less common than the old "why spend so much money on space when we have so many problems here on Earth" line, which I feel is effectively dealt with by a combination of pointing out that humanity is actually capable of doing more than one thing at a time, that sometimes the solutions to problems on Earth can be found in space (and this is going to become more true rather than less true in the future as land and resource pressures on Earth mount), and finally that we really can spare the money - the total amount spent so far on the war in Iraq could have paid for a complete repeat of the Apollo program (including R&D costs) with $500 billion left over to spend on the environment, poverty, hunger, education and whatever else you care to mention.

Viewing the fact that we've already been to the moon as an argument for never going back confuses space exploration as something done purely for prestige, entirely as a stunt, a game of ticking boxes with no further meaning or purpose. Admittedly this attitude played a strong role in the original space race, with a desperate desire to show up the commies fuelling most of what NASA did, but in 2010 it's entirely out-dated and nobody should cling to it anymore. We've been to the moon, yes, but we haven't yet even scratched the surface of what there is to do on the moon! We haven't done a fraction of the meaningful geological research that could be done on the moon: research which can help to improve our understanding of the formation and history of the solar system, including Earth. We haven't set up observatories on the far side of the moon to take advantage of a complete lack of light pollution or atmospheric distortion. We haven't prospected for valuable Helium 3 in the lunar soil. We haven't tried growing edible plants in the lunar soil. We haven't tried performing industrial processes on the moon which will work much better and much more cheaply in the reduced gravity. The list of interesting stuff we haven't done goes on. Many would argue that most or even all of the above could be done by teleoperated robots from Earth at a lower cost than it could be done by people. This is undoubtedly true, but doing it at least partly with people has the benefit of providing much needed practice for the establishment of future long-term colonies on the moon for their own sake. Seeing permanent off-Earth human presence is essential for guaranteeing the very-long-term survival of the human race, and should always be considered the ultimate goal of manned spaceflight.

Some people who are in favour of off-Earth colonisation would argue that the moon is a bad place to do it. It's true that if we just had to pick somewhere in the solar system as a starting point for off-Earth human presence, based entirely on how nice various places are to live, the moon would probably not end up high on anybody's list. It has no atmosphere, no magnetic field, very low gravity, not a whole lot of water, and unless you're in one of a few special places, you can't rely on solar power easily because night time lasts 14 days. It makes a lot more sense to head for Mars, and arguably even more sense to head for the atmosphere of Venus (although this idea has a lot less currency amongst space enthusiasts, for some reason). However, the simple fact is that moving humanity off the Earth is not a simple matter of choosing somewhere to go and then going there. We have to deal with the practical matters of actually getting and living there. The moon is 3 days away from Earth using existing technology, meaning that rescue missions and emergency resupplies are actually feasible: contrast this with months of travel for Mars using existing technology. The radio delay to the moon is a little less than 2 seconds, compared with about 15 minutes for Mars, reducing the psychological feeling of isolation and allowing real time problem-solving assistance from specialist teams on Earth. Landing on and taking off from the atmosphere-lacking moon is a completely solved problem which we've done before, whereas the same problems on Mars are a lot harder and it's by no means certain the techniques we use for probes and rovers will scale up to vehicles large enough to support a human crew. Even though Mars is a nicer place to be than the moon, getting to and living on the moon is going to be considerably easier than doing the same on Mars for the forseeable future, and since there are still so many unanswered questions about living off-Earth - what are the long term physical and psychological effects of reduced gravity, of increased radiation exposure, of living so far away from the rest of humanity? - it makes sense to me that we should try to answer these questions in the very near future on the moon, at the same time as we work on getting everything else we can get out of the moon in terms of science, resources and industry.