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NASA Developing Small Nuclear Reactor For the Moon
Posted by
CmdrTaco
on Thu Sep 11, 2008 09:16 AM
from the because-they're-nasa dept.
from the because-they're-nasa dept.
marshotel writes "NASA astronauts will need power sources when they return to the moon and establish a lunar outpost. NASA engineers are exploring the possibility of nuclear fission to provide the necessary power, and they are taking initial steps toward a non-nuclear technology demonstration of this type of system."
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Can't wait to see... (Score:5, Funny)
Re: (Score:3, Interesting)
Re:Can't wait to see... (Score:5, Insightful)
The same thing that happens to everything else we brought to the moon that we didn't also use to get people/objects back. It's going to sit there. It's not like it'll be hurting anybody/anything either.
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Re:Can't wait to see... (Score:5, Insightful)
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Re:Can't wait to see... (Score:5, Funny)
One big problem with putting a slingshot on the moon capable of achieving escape velocity. I read an analysis [wikipedia.org] on the topic several years back:
First we establish the means of hurling stuff off of the moon sufficient to achieve escape velocity. Soon we realize the potential of using that mechanism for mining and establish a mining colony. Miners realize that, after several years in 1/6 gravity, they cannot return to Earth and their resources are being irreversibly diminished because hurling ore at Earth is much cheaper than hurling water at the moon. Through the aid of an advanced computer, they decide to declare war and start "throwing rocks" at us.
Sure, moon culture may turn out to be pretty cool and incorporate some groovy polygamy, but nobody wants a rock war.
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Re:Can't wait to see... (Score:5, Funny)
Paper beats rock, and we have plenty of trees here on Earth. We can't lose!
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Re:Can't wait to see... (Score:5, Funny)
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Re:Can't wait to see... (Score:5, Interesting)
I'm not going to be bothered with the math nor will I try to defend Heinlein's supposition that large loads would produce mushroom clouds upon impact.
But, an object that leaves the moon at roughly escape velocity will be moving much faster by the time it hits Earth's atmosphere. You've got quite a bit of potential energy relative to the Earth just by being so high above the surface - That's quite a long fall with no air to slow you down. You can't factor in strictly the kinetic energy from the launch.
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Re:Can't wait to see... (Score:5, Informative)
Um let's see...
m = 1 kg
v = 12 km/sec = 12000 m/sec
KE = 1/2*m*v^2 = 1/2 * 1 * 12000^2 = 72 MJ for a 1kg object
I was always happy when my lab partner and I came within an order of magnitude of the correct answer in my EE lab.
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Re:Can't wait to see... (Score:4, Funny)
if only the sun would stop moving...
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Re:Can't wait to see... (Score:5, Funny)
And if only it were massive enough to materially affect the trajectories of the planetary bodies near it!
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Doesn't work (Score:5, Funny)
In the thin/nonexistent atmosphere of the moon, the rubber bands dry out and crumble quickly.
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Re:Can't wait to see... (Score:5, Informative)
Well the sun is a hellish inferno of radiation as it stands, dumping a million tonnes of the nastiest crap we can find into it would be like spitting into niagara falls.
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Re:Can't wait to see... (Score:5, Funny)
I personally think it's easy to send things into the sun because I've never had to do it before and it always works great for superman. Also because I rarely figure out the calculus and physics behind wild "what if" scenarios. What's the fun in that?
It's jerks like you who make foreign policy boring by saying stuff like "Yes we could invade Iraq, but then what would we do about the insurgency, building democracy blah blah blah I hate america." Let us build the ever loving nuclear reactor on the moon then chuck it into the sun when we're done with it! Next you're probably going to whine about how tax dollars might better be spent on education or some crap like that!
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Re:Can't wait to see... (Score:5, Funny)
The reactor is going to explode and contaminate the moon, turning it into a place where a human cannot survive without some kind of protective clothing. Clearly, this is unacceptable.
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Re:Can't wait to see... (Score:4, Funny)
Dude, you got it wrong. The reactor is going to explode, sending the moon out of Earth's orbit [wikipedia.org]. Moonbase Alpha [wikipedia.org] will boldly go where no man has gone before. Exploring space one crazy alien at a time.
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Oooh nuclear... scary... (Score:4, Informative)
The same thing that the SNAP-27 RTGs (radioisotope thermoelectric generators) did on the moon since the Apollo 12 (and other Apollo missions) landed on the moon.
They are still there and for many years preformed unmanned experiments on the moon surface after the astronauts left studying moonquakes, meteor impacts, temperature, magnetic field, atmosphere, and gravitational field in addition the long term feasibility of RTG study.
http://en.wikipedia.org/wiki/Systems_Nuclear_Auxiliary_Power_Program [wikipedia.org]
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Re:Can't wait to see... (Score:4, Insightful)
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At least getting rid of the waste won't be hard (Score:4, Funny)
Unless the NIMBY crowd change to NIMOrbit
Re: (Score:3, Funny)
Cmon, you never saw Space: 1999? It's a disaster in the making!
(On the other hand, there's Catherine Schell...)
Re:At least getting rid of the waste won't be hard (Score:4, Informative)
You do realise there is more land area on the moon than on earth? Plenty of space to leave things for a good time.
I agree with your conclusion, but your premise just plain wrong [wikipedia.org]. Sorry.
The surface of the Moon is less than 1/10th that of the Earth, and only about a quarter the size of the Earth's land area (or about as large as Russia, Canada, and the U.S. combined).
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Dupe! (Score:5, Funny)
http://en.wikipedia.org/wiki/Space:_1999 [wikipedia.org]
Asking for trouble... 'cos this didn't work out too well for Moonbase Alpha.
Re:Dupe! (Score:5, Funny)
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Yes! This can be a source of power! (Score:4, Funny)
Umm, water? (Score:4, Insightful)
Re:Umm, water? (Score:5, Informative)
I think it depends on the reactor type. Some can use liquid sodium, etc. Think "micro-reactor" similar to the proposals by the Japanese space program or Toshiba for small output, "4S":
http://en.wikipedia.org/wiki/Toshiba_4S [wikipedia.org]
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Re: (Score:3, Informative)
That's how it's done normally, yes; and I assume this reactor will work that way (although I suppose capturing thermal energy and cooling the core are both tasks for which you could design a water-free approach if you wanted to).
Now, if only we had a way to transport a necessary material from here to the moon... but alas, we'll have to build the reactor entirely using materials already there...
(Ok, well, I think I'm funny anyway...)
FWIW, I'm pretty sure you could send a finite amount of water and just keep
Re:Umm, water? (Score:5, Funny)
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Re:Umm, water? (Score:4, Informative)
An RTG is not a reactor. It does not "split uranium". In fact, RTGs don't use uranium as it's not radioactive enough. RTGs also produce a LOT less power than reactors. The last ones sent to the moon with the Apollo missions generated a mere 60 watts. These new reactors will work on actual nuclear fission and are intended to generate 40 kilowatts. A 600x increase in power output.
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Send Homer. (Score:5, Funny)
Not solar? (Score:5, Insightful)
I'm hoping someone can explain to me why the far better-established and easily-maintained option of Solar Power isn't first on the list.
I mean: negligible atmosphere, established support-structure (the ground), 100% predictable yield, negligible material costs after setup, and land-area isn't such a big issue... can't really think of a better case for it.
Re: (Score:3, Insightful)
Re:Not solar? (Score:4, Insightful)
A 40 KW nuclear reactor is about the tiniest nuclear reactor imaginable. I'm sure NASA isn't considering it because of its power density or its mass. Each one of the solar panel assemblies on the ISS could potentially generate 32 KW. The problem is the 28 day lunar 'day.' Solar power plants on the moon will see a significant drop in power during the lunar night (about 100% of rated power at most locations except perhaps the poles). Therefore, long duration missions would require batteries. Supplying 40 KW for 14 days would require massive batteries (and also more than 80 KW of solar arrays). Based on my back of the envelope calculations, you would need something about 3 times the size of the Fairbanks Battery Backup [wired.com]. Additionally, nuclear power is more scalable. Knowledge gained with operating tiny nuclear reactors on the Moon could also be used with larger reactors that far outstrip any potential competition by solar power.
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Re:Not solar? (Score:4, Informative)
As for the reactor life, I'm betting 10-30 years with the included fuel, and it is probably not meant to be serviceable. I get the feeling those who don't know much about nuclear reactors think that there are these big, daily freight trains, like with coal plants, but full of uranium. Fact is, nuclear power isn't all that resource-intensive.
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Re:Not solar? (Score:5, Insightful)
Solar cells don't last forever.
In a space environment, I believe the power output from them drops by 5% every year. Solar cells on earth don't degrade that quickly because they aren't exposed to the same amount of radiation.
Also, once the solar cells have degraded, thats it. You can't repair them, they must be replaced. A nuclear reactor could have new shipments of fuel sent up.
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Re:Not solar? (Score:5, Insightful)
I'm hoping people will RTFA before asking stupid question...
Returning to the moon is a dry-run for going to Mars. Mars is further away from the sun, and has lots of nasty dust storms.
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Re:Not solar? (Score:5, Informative)
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Re:Not solar? (Score:5, Funny)
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Re:Not solar? (Score:5, Informative)
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Re:Not solar? (Score:5, Insightful)
The ISS has an acre of solar panels, and they can be designed incredibly light-weight because they are in microgravity. Panels on the moon would require vastly more infrastructure to support them, which would increase the weight and bulk considerably.
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this idea is lunacy (Score:3, Funny)
you have to be a lunatic to put fission on the moon. it seems once a month i encounter some sort of hairbraned scheme like this. i wish there were a silver bullet solution to these sort of moonbat ideas
Design from scratch? (Score:3, Insightful)
LIttle matter of cooling (Score:4, Interesting)
Eh, any idea how they'd cool the thing? It's fine to split atoms to make heat, but on the Moon you need to have a closed-loop cooling system. So you have to cool off the turbine exhaust so you can feed it back into the reactor. Problem-- no atmosphere and no lakes or rivers to carry away the heat. No groundwater either. Many many many meters of loose insulating moon-dust and rock fragments before you get down to bedrock, which in itself is not all that great at conducting away heat.
Methinks the Moon is not a great place to be running a reactor or power plant of the heat-cycle variety. Maybe solar cells.
Re: (Score:3, Informative)
well, if the moon (and all of its nuclear waste) falls onto the earth, I'm pretty sure the radioactive bits won't be the first thing on people's minds.
Re:Confused on Nuclear waste (Score:5, Insightful)
Getting anything into space, and all the way out of earth orbit, is monumentally EXPENSIVE.
Digging a big hole in the ground is monumentally CHEAP (at least in relative terms).
The people you've heard from, that are scared of sending radioactive material into space, are monumentally STUPID.
Also, fissile nuclear material is a highly valuable, relatively scarce, and non-renewable resource. It's more than likely that we'll need to dig that stuff up again in a century, and reprocess it. Quite a bit harder to do so if it's on it's way to Pluto.
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Volume (Score:5, Informative)
A 40kw reactor like they discuss in the article would use a small amount of uranium, probably less volume of radioactive material than used for the RTGs in the cassini probe. Whereas we have tons and tons of nuclear waste to dispose of, not just spent fuel rods, but reactor internals, coolant, and so on.
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It's not really waste (Score:5, Informative)
Nuclear waste is not really waste. It simply needs to be used in a different reactor. Storing this waste and doing nothing with it is really a waste.
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Re:Confused on Nuclear waste (Score:5, Insightful)
Because it is a horrifically bad idea.
Nuclear waste is not waste, it is nuclear fuel that has been partially used, but still retains 90% or so of its functionality. Using feeder breeder reactors we could easily reprocess this "waste" while generating close to 10 times the energy of a standard nuclear reactor (for the same amount of fuel) while producing waste that is only potentially dangerous for a few hundred years, vs potentially thousands of years.
The only problem is that people are dumb. And the idea of building anything nuclear (pronounced Nook you ler) invokes the same kind of response as declaring that you worship satan in a southern baptist church.
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Re:Goodbye Earth, Goodbye Moon (Score:5, Insightful)
Assume, for a moment, that the LHC destroys the Earth by turning it into a black hole. Know what would happen to the moon?
The Moon would be unaffected. It's just as happy to orbit a 5.9736*10^24 kg black hole as it is to orbit a 5.9736*10^24 kg planet.
Black holes are just gravity, people. The only difference between them and anything else with mass is that you can get closer before you hit the event horizon than you could get before you hit the surface.
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Re:A note of reality injected here (Score:5, Informative)
How about some perspective on that reality?
http://en.wikipedia.org/wiki/Image:Fy2008spendingbycategory.png [wikipedia.org]
Here's a hint: The NASA slice is the 0.6% one. Double NASA's budget and you're still not up to the level of "Other Off-Budget Discretionary Spending."
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