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NASA's New Mission to the Moon
mattnyc99 writes "Popular Mechanics has a new, in-depth preview of NASA's Orion spacecraft, tracking the complex challenges facing the engineers of the CEV (which NASA chief Michael Griffin called 'Apollo on steroids') as America shifts its focus away from the Space Shuttle and back toward returning to the moon by 2020. After yesterday's long op-ed in the New York Times concerning NASA's about-face, Popular Mechanic's interview with Buzz Aldrin and podcast with Transterrestrial.com's Rand Simberg raise perhaps the most pressing questions here: Is it worth going back to the lunar surface? And will we actually stay there?"
If we went back to the moon, I assume NASA's plan to would be to discover water so eventually the moon could be a docking station for trips to mars!
Lol. Many, many reasons.
Yes, there's the lifeboat argument.
There's doing research and rehearsals for manned exploration further out. I certainly wouldn't want to venture to Mars or the asteroids without technology tested a little closer to home first.
Raw materials -- He3 (as fusion fuel) is one possibility. As a source for raw materials (silicon, aluminum, etc) for building solar powersats is another.
Astronomical research -- lunar farside is the best place in the solar system for radio telescopes, it's shielded from Earth's noise. It's also a pretty good place for telescopes at all other wavelengths, especially if there's a manned base to swap out instruments, repair cameras, etc.
A frontier. People need one, even if only a few actually pioneer it. Earth will go crazy even faster without one.
Whole books have been written on "why", a Slashdot comment isn't going to do it justice.
-- Alastair
There's an interesting article on what the space program could've look like if the Saturn V rocket program wasn't cancelled. The new program will be just a shadow in comparison.
The Moon is like Iceland - easier to get to from Europe but there's not much there besides scenery. The Mars system (Mars, Phobos, Deimos) are New York City, Boston and Philadelphia. I guess this makes Mars-Earth L1 the Hudson River?
The resources to build an entire civilization exist on/around Mars. The moon is a fossil world.
We can learn some from Luna, and probably take the first steps to colonization there, but the real action is going to be on Mars. There is a lot of planet-specific engineering that needs to be done for either location. Lunar spacesuits won't work on Mars, there will be huge differences in sealing technology and energy generation (you can burn silane as internal combustion on Mars, for instance). We can learn as much in high orbit or at a NEO about colonizing Mars as we can on the Moon. Almost all technical development for any near-term colonization is going to be developed on Earth, though.
If I had several Billion $$ right now, I'd commision a Russian-Bigelow spacecraft for a human mission to Phobos or Deimos. This is the ideal target for early development, energetically close to Earth, resource rich and within telepresence range of Mars. We can mine water and ship it back to LEO using technology we have now, or nearly. Russian companies have decades worth of human habitat experience, Bigelow would provide the main living space, custom tools purchased from best providers. The project would mine water and provide realtime control for robots throughout cis-Mars.
gigantino.tv - Heavy but weighs nothing.
OK, so we shouldn't be testing things that could end up with a grey goo on the moon any more then on earth. We shouldn't try to build a bomb that could crack a world. But it really takes an effort to destroy a big rock in space in any meaningful way. What about experiments with bacteria and viruses that could (if we mess up *and* they escape) could kill everyone, or fusion power or exotic elements and crap like that? What if you wanted to use a virus to kill cancer but you weren't sure if it could easily mutate and kill regular cells as well. A nice place like the moon could prevent accidental genocide while you did some long term tests.
The nice thing about the moon is that if accidentally release a huge cloud of radiation we just get a green moon instead of a black moon when it isn't lit by the sun, whereas on earth we would have hundreds of miles of radioactive wasteland that could otherwise be a nice place to live. I mean it would still kinda suck long term if we teraformed the moon (in the long term), but it would still not be nearly as bad as on earth.
Does a line appended to your comment give your post meaning in and of itself, or only in relation to those without?
This could be considered slightly offtopic, but I would add one more benefit of NASA Moon mission: the resurrection of public interest in space science (in general) and Space Science Fiction (in particular). Did you notice that during recent decades the theme of science fiction shifted significantly from space exploration plots to fantasy and alternative history? As a big fan of space science fiction, I feel my favourite trend is neglected. The reason is obvious - the whole space research both in USA and Russia/Europe fell into stagnation and public interest was lost. Remember how excited the science fiction writers were about space technology back in 60s? They were expecting humans to fly around solar system by 2000 and to distant stars in the beginning of this new century. Where are their hopes? Ruined. Now I really hope NASA mission will bring back the long-forgotten public excitement about space exploration, and the science fiction will once again picture the starships instead of dragons and elves. I hope.
One time, yes you do. But you also need to do that for a shot straight from earth. So that's pretty much a wash, agreed? The problem comes from multiple moon ->mars shots.
Certainly you can, and yes there is. Think about the basics. What is a space drive, generally speaking? It is a device that expels [something] in the opposite direction from that which you desire to go. And how do we get some of the highest exhaust velocities we've ever attained? Ion drives. Electricity. Ion drives expel stuff [any stuff that will hold a charge] using electricity. And is there electricity on the moon? Think solar panels, and the answer, of course, is yes. Right now, Ion drives are limited in thrust, but they are *very* efficient. That's one useful approach, and there's nothing to say we won't improve them hugely. They're really excellent space drives because they can keep adding thrust on a continuous basis; they use less reaction mass because they can attain such a high exhaust velocity. They're low, constant thrust.
But wait... How do you get anything off the surface with a low thrust engine? You need more power than an ion drive, right? Yep. Can you do it electrically? Sure. You can use a linear accelerator. Again, purely electrical technology, and you can fling things at astounding velocities. The longer the accelerator, the more human-freindly the acceleration will be. Short tracks require high G's, and we hate that. Anyway, again, it's down to electricity and nothing else. No need to lift anything out of the earth's gravity well, once the system is running. We're doing better and better at capacitive storage, and batteries will soon fall to ultracaps, or at least, that's how it looks today. Solar panels are getting less and less expensive, and more and more efficient, and silicon... is there silicon on the moon? Yep. There is. :-)
And landing? Next, there are space elevators. We've got some really tough technical issues trying to build a space elevator on earth. The materials strength to gravity well challenge is just about at the edge of what is possible. But on the moon, this isn't at all the case. 1/6th the gravity means, pretty much anyway, 1/6th the problem. You can bring all manner of cargo up and down at absolute minimum cost and a reasonable constant energy expenditure. After all, space vessels should probably remain in space; it isn't them we want to get from here to there, it is the cargo. Space elevators are also much happier when there is no atmosphere; they just sit there. No blowing around, etc. On Mars, while the gravity is in your favor there, the atmosphere might be a little annoying. Still, it's more doable than it is here on earth.
It's like anything else. You have to spend to build the infrastructure required to get things running on their own, but once that's done, then the returns defray, and eventually eliminate, the original investment. But it doesn't have to be an infinite loop of bringing things from earth to the moon. There are plenty of creative solutions to these problems - I'm not saying they aren't problems - and in the end, there is every reason to think we can pull this off and make it work, and work well.
There are enormous amounts of natural resources out there. We should go get them. We should land and establish bases everywhere we can. We should explore, because knowledge rarely proves useless, and because a lot of us like to explore. The more resources we pull from space, the fewer we'll need to pull from the earth. Delivery of raw materials from space is pretty trivial, basically let gravity do it; the main thing, I would think, is to make them come in gently enough so as not to cook the atmosphere in the process, and avoid scattering them on impact. Water landings and gliding bodies come to mind. But that's not my area of expertise. :)
I've fallen off your lawn, and I can't get up.
Well, maybe not fuel, but you can make all the oxidizer you could ever need, and that's the more important half.
72% by weight of a typical Kerosene/LOX rocket engine is oxygen. And the soil/dust/regolith on the Moon is mostly oxygen. We just need to perfect automated methods of extracting the oxygen from the soil, but that's an engineering problem, and not a showstopper.
Not exactly. You burn some fuel to bring a small amount fuel from Earth to the Moon, and don't bother to bring oxidizer. Then you combine the fuel you brought with LOX you harvested from the surface of the Moon, and launch to Mars with that. Since you're only leaving a 1/6g gravity well, you will need far less fuel to leave the moon and go to Mars than you would to leave Earth and go to Mars, assuming you left during the launch window when the Moon has a higher orbital velocity with respect to Mars than the Earth does (which happens about once a month). All this adds up to an energy savings.
Of course, this all requires some sort of infrastructure to work, like a moonbase, and that will be expensive to build. But once the infrastructure is in place, the long-term energy savings are substantial, especially if we start doing things like harvesting objects outside the Earth's gravity well for the other half of the fuel/oxidizer ratio. There's water in comets--that's a hydrogen source. Most asteroids have the same composition as Carbonaceous chontrite meteorites, which are chock full of organic compounds--these can be cracked open to collect both hydrogen and nitrogen. Hydrogen can be burned by itself or combined with oxygen to make hydrogen peroxide (a low-energy monopropellant used in some thrusters). Nitrogen can be combined with oxygen to form dinitrogen tetroxide (a decent rocket fuel that requires an oxidizer) or with hydrogen to form hydrazine (a high-energy monopropellant). I'm sure people with more experience in chemistry and astronomy can suggest many other possibilities as well.
The bottom line is, there's lots of fuel available out in the solar system, outside the big gravity wells, and taking advantage of launching from a small gravity well using fuel harvested from other small gravity wells will result in a substantial energy savings.
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