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NASA Developing Small Nuclear Reactor For the Moon
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."
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
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.
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.
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.
Except for the fact that it would be dark at your moonbase for nearly two straight weeks at a time, solar power would be great.
Sig this!
You'd need a great battery technology to survive a two week night. Split hydrogen for fuel cells?
Night time on the moon is kinda long (weeks). What do you do then? Batteries that can store weeks worth and PV arrays that run at over 2x capacity are not really going to work all that well. Well not as well as a 24/7 nuke plant.
If information wants to be free, why does my internet connection cost so much?
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.
Javascript + Nintendo DSi = DSiCade
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).
The World Wide Web is dying. Soon, we shall have only the Internet.
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.
UNIX/Linux Consulting
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.
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. 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).
He's getting rather old, but he's a good mouse.
How about some perspective on that reality?
http://en.wikipedia.org/wiki/Image:Fy2008spendingbycategory.png
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."
IWARS.
People, in general, disappoint me. Politicians even more so.
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.
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
That's actually exactly what they are doing for micro-reactors. They are not classic mechanical "liquid+heat->steam->liquid+electricity set-up but strait heat->electricity via thermoelectric elements.
I'm aging rapidly, I bought a new game and had no idea if my machine was good for it.
Much as I loved the story, I'm disappointed that Heinlein didn't do the basic math on his rocks. Objects moving at marginally over escape velocity (12 km/s or slightly less, depending how much excess the launcher can supply) have 7.2 MJ/kg of kinetic energy (0.5*m*v^2). TNT has 4.2MJ/kg of chemical energy. So, while the rocks are certainly potent weapons if you can aim them accurately, a few tons or even tens of tons of rock, at < 2x TNT equivalent, isn't even close to the nuclear blast that Heinlein makes them out to be comparable to.
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.
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.
... to test a Liquid Metal Fast Breeder Reactor. 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 here on Earth, but there's still too much flat-out wrong information floating around for them to be accepted.
Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
Just as an approximation, it would leave the moon at just over the moon's escape velocity, slow to nearly zero, then accelerate before hitting to pretty near the Earth's escape velocity. (Seven miles a second, isn't it?)
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
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