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NASA Developing Nuclear Reactor For Moon and Mars
Al writes "NASA recently finished testing a miniature nuclear reactor that would provide power for an astronaut base on the Moon or Mars. The reactor combines a small fission system with a Stirling engine to make a 'safe, reliable, and efficient' way to produce electricity. The system being tested at NASA's Glenn Research Center can produce 2.3 kilowatts and could be ready for launch by 2020, NASA officials say. The reactor ought to provide much more power than solar panels but could prove controversial with the public concerned about launching a nuclear power source and placing it on the Moon or another planet."
The uranium that goes into a reactor isn't all that radioactive - it's the spent fuel that comes out that's the problem. If a rocket carrying this thing explodes on take off it isn't going to be Chernobyl. In fact, it sounds a good deal safer than all those Pu-238 RTGs that have been sent up there.
It's a Stirling Engine....not Sterling.
An engine made out of silver? Or just a generally excellent one? Ah, a Stirling engine.
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This is the most intelligent comment on this thread so far, why it is posted as AC I cannot imagine. It reminds me of a brilliant comment on the assembly of nuclear fuel rods: that they are so nonradioactive that they can be assembled by hand. The operators wear gloves, not to protect them from the fuel, but to protect the fuel from their fingers.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
Read the article. 2.3 kW is the test version, they want to scale it up to 40 kW for the base:
The recent tests examined technologies that would see a nuclear reactor coupled with a Stirling engine capable of producing 40 kilowatts of energy--enough to power a future lunar or Mars outpost.
40 kW is approximately 17 outlets that can handle 20 A at 115 V. Yeah, it's still not a ton but it's a start and you could potentially put up several of these reactors as you expand the facility. This would also add fault-tolerance to the entire system.
Sapere aude!
Kind of like how letting wood rot is not burning it.
Uranium is "huggably safe" before a reactor is actually turned on. With a half-life of a billion years it's more dangerous as a heavy metal than anything else.
Plutonium is nasty if powdered or vaporized, but NASA designed a "safe" for the Cassini plutonium RTG that would survive being dropped at any point during the launch path.
The hydrazine fuel used in the maneuvering thrusters in spacecraft and the Space Shuttle's APUs is amazingly toxic. In most scenarios a tank of hydrazine is more of a danger than a lump of plutonium. Off-Earth, a hydrazine APU is just exposing astronauts to unneeded danger to avoid "scary nuclear scary scary".
Socialism: a lie told by totalitarians and believed by fools.
Actually, Moon dust is a bigger problem on the than Mars dust exactly because there is no weather. Weathering wears down the rough edges of dust particles. Without it, the dust retains jagged edges. It is extremely abrasive, sticks to everything, and is electrically charged. Once it sticks to something, it is extremely difficult to get off. On Mars, however, you can just wipe the dust away. It's weathered and smooth, like the dust we are all familiar with on Earth.
http://www.wired.com/science/space/news/2005/04/67110
http://www.sciencedaily.com/releases/2008/09/080924191552.htm
http://www.space.com/scienceastronomy/090421-st-moon-dust-sunangle.html
Hydrazine is not all that bad compared to the oxidizer used, nitrogen tetraoxide. People used to sniff for hydrazine leaks with their nose (smells like rotten fish) early in satellite development. Nitrogen tetraoxide smell like the inside of your nose being dissolved.
But your general point is correct in that the chemical effects of most of these items are far more problematic than the radioactivity, and the chemical effects can be dealt with reasonable safety as has been proven for decades.
Brett
"which is ot that hard"
Okay, how?
Batteries are heavy and you have to lift them from Earth. Regolith has a pretty low specific heat capacity. Water works pretty well to store heat, or to make hydrogen, but on the moon you're probably not going to have much and you might want to drink it instead. You can compress gas to store energy, but where are you going to find that on the moon?
What is it about "nuclear" that makes people's brains turn off?
The same mindset, I guess, that prompted the medical profession to quietly change the name of Nuclear Magnetic Resonance Imaging (NMRI) to Magnetic Resonance Imaging (MRI). Nobody wanted an NMRI but now people line up for an MRI, at least here in Canada.
Since there is specifically zero atmosphere, the only dust you're going to get on the rover is something directly applying it via ballistic trajectory. That's pretty easy to prevent with simply placement slightly away from drive paths. A wind driven environment will *always* have more dust flying around than the moon. there isn't any atmosphere to push it so it just sits until something imparts energy to it.
That's an impressive and very persuasive bit of reasoning with only the minor flaw that it's entirely wrong from beginning to end. The fact is lunar dust is very pervasive, fine, and troublesome. Here's an article about it.