NASA Developing Small Nuclear Reactor For the Moon 431
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."
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]
Re:Umm, water? (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 using it in a closed system.
Re:Confused on Nuclear waste (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.
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.
Re:Not solar? (Score:5, Informative)
14-day nights (Score:3, Informative)
Re:Not solar? (Score:5, Informative)
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.
Re:At least getting rid of the waste won't be hard (Score:3, Informative)
Remember, though, this is the Moon. Unlike on the Earth, the waste isn't going to be blown around by the wind or leached out by groundwater and carried into drinking water supplies. There's not going to be some giant moonquake to destroy the structural integrity of the disposal site. Your biggest risk is being at the center of a new crater, and that's kinda low.
So give a guy a shovel - or whatever they'll be using to dig foundations for the lunar base - and put it in a hole a few feet deep, stick up a sign, and don't go near it if you don't have to. It's not like they have tons and tons of it that they can contaminate millions of square miles with it (this is a small reactor). And it's not like there aren't other environmental radiation hazards (radiation from stuff that the magnetosphere doesn't block).
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.
Sub critical assembly? (Score:1, Informative)
The problem with solar on the surface of the Moon, is that daytime is 2 weeks and nighttime is 2 weeks. What happens if your backup store fails and it is night?
A reactor the size of an office trashcan, sounds very much like a Canadian SLOWPOKE (which is 16 kW thermal). Which is a subcritical assembly. It requires a reflector and a moderator to become critical, and is inherently safe. The amount of uranium in the core is less than what is required to make a bomb, quite a bit less. SLOWPOKEs can go decades between refueling. This NASA idea is a bit bigger at 40 kW thermal. The core is "just another piece of metal" until it is made critical the first time. Getting it into space isn't a problem. Once it has been started, you probably do not want to bring it back to Earth. However, to dump an old core into the Sun from the Moon is probably a much safer prospect than getting rid of nuclear waste from Earth by dumping it into the Sun (which people have proposed in the past). It is probably better just to leave it on the Moon if you need a new core in 30 years or whatever. I would expect that refueling is the same, just put in a new core. Much more like disposable batteries than the refueling of a power reactor on Earth.
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).
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."
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.
Re:Can't wait to see... (Score:1, Informative)
Yes, the real problem is : what happens if the shuttle/rocket used to bring it too the moon explodes in the atmosphere ?
We already have satellites/probes powered by nuclear decay of plutonium iirc
Re:Umm, water? (Score:3, Informative)
Re:Can't wait to see... (Score:1, Informative)
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.
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.
Perfect place... (Score:3, Informative)
... to test a Liquid Metal Fast Breeder Reactor [wikipedia.org]. No oxygen to support combustion of the liquid sodium, and high efficiency so that you don't have to refuel it as often.
I'd love for us to use these [nationalcenter.org] here on Earth, but there's still too much flat-out wrong information floating around for them to be accepted.
Re:Can't wait to see... (Score:3, Informative)
Re:Goodbye Earth, Goodbye Moon (Score:2, Informative)
A black hole as small as the Earth would not be stable. Contrary to what that Disney film will tell you, black holes DO emit energy, and a small one will rapidly shrink until it's too small to maintain itself.
In short: You can't have a small black hole that stays around. It will evaporate.
http://en.wikipedia.org/wiki/Hawking_radiation
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]