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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."
"We are not building a system that needs hundreds of gigawatts of power like those that produce electricity for our cities," says Don Palac, the project manager at NASA Glenn Research Center in Cleveland, OH. The system needs to be cheap, safe, and robust and "our recent tests demonstrated that we can successfully build that," says Palac.
I read this as, "the system needs to come in at no more than half the cost of a gigawatt power plant". I'm all for space travel, but I can't help but flinch when I hear somebody at NASA say "cheap".
Then they can give the reactor to me and I can finally send the power company a photocopy of my ass; I don't even have to worry about disposal! I hear there are plenty of countries like Iran and North Korea looking for nuclear refuse.
Nuclear power is actually one of the safest, cleanest, and most reliable forms of power ever invented. So long as no meteroites hit it, we should be fine. Huh. Wonder what caused all those craters on the moon.....
My blog
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 shouldn't be more controversial than the reactors that powered Voyager and other deep space probes. There have been protests over some of the more potentially dangerous reactors that might have caused contamination over a wide area if they blew up; but IIRC they launched anyway.
A reactor that small shouldn't require a huge ammount of fissile material. I bet it could blow up in the atmosphere and produce less radiation than we get from a day of coal fired power in the Eastern US. Coal is full of trace radioactive elements, and it adds up when you burn as much as we do.
For all intensive purposes, "whom" is no longer a word. That begs the question, "who cares"?
It's a Stirling Engine....not Sterling.
An engine made out of silver? Or just a generally excellent one? Ah, a Stirling engine.
More quality editing from Slashdot...
The specs would have this thing lasting 8 years.
And yeah, the sun does run out. Or at least it isn't useful when it goes through an extended night. Or if it is in a location that doesn't get direct sun (crater).
See my journal for slashdot ID's by year. Mine created in 2005. http://slashdot.org/journal/289875/slashdot-ids-by-year
Stirling from the name of inventor - Dr. Robert Stirling.
That's one standard kitchen outlet in North America. You could run a coffee maker and a microwave, but not a whole lot more...
How much does it weigh in total (including shielding etc)?
Ian Ameline
The Moon's "Day" is 28 days long. Unless you are on the poles, you have to have enough battery power for around 14 days of darkness. That said, a giant rotating mirror at one of the poles could provide a lot of power, and you could use a Stirling engine to convert the heat to electricity.
All ideas^H^H^H^H^Hprocesses in this post are Patent Pending. (as well as the process of patenting all postings)
Yeah, until the fuel runs out. I'm pretty sure that with solar panels, the sun never runs out.
I'm 100% sure you are wrong.
0 = 1 + e^(Alt something)
All of our inhibitions about nuclear power is why we are doomed. Actually even wrote about this previously... the real danger to the west is not nuclear proliferation from atomic bombs, but from third world countries adopting nuclear mining, nuclear aircraft, nuclear ships, and nuclear spacecraft and pretty much leaving the west behind in a windmill driven green feel good stone ages.
This is my sig.
Why not re-open research into nuclear thermal rockets? They were able to get them up to 40% efficiency back in 1972, I'm would hope we can do better than that now. Use the reactor to heat a propellant to get you to the moon, then use the reactor on the moon to power the base. If it's time to head home, you only need to ship a relatively stable propellant up, rather than actual rocket fuel.
Yeah we can't have dangerous, dangerous radiation in space. Think of the children.
Solar panels are great until they get dirty or worse damaged by micro-meteorites. Plus you might not have light 24/7 when you are on a large body like mars so you gotta add lots of batteries for your Solar panel setup unless you're ok with only breathing during the day...
When I first saw this, I thought it was for powering VASIMR plasma engines.
Recently, AW&ST had an article suggesting that transit times between Mars and Earth 30 days could be possible using a continuously running VASIMR engine (it has an insanely high specific impulse). BUT, it would require a nuclear power source because the amount of solar panels (especially outside of earth's orbit) woudl be impractical.
myke
Mimetics Inc. Twitter
1. Ignorance.
2. The Internet
There is a whole lot of people who can now be offended at things they would never have heard of before or hand reason to be offended of. Never under estimate the ability of humans to make ignorance even more prevalent. What many thought would free us from ignorance only seemed to exaggerate it more.
I guess there is another option, it never ceases to amaze me how many people can find offense in anything. I think they have a need to be noticed or to find a way to blame others for any condition they are in.
* Winners compare their achievements to their goals, losers compare theirs to that of others.
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."
Why isn't NASA looking into technology to exploit the temperature difference between lit and shaded areas on the moon to generate electricity? That should be an excellent source of power most of the time.
Ok, great, they put the heat in one side of the Sterling Cycle Engine, and it moves to the other side and we get motion, but what do they do with the heat? There's no air/water to bump against a cooling fin to get the activity of the molecules. Does the "icy vacuum of space" actually cool things very well?
If it did, why wouldn't a sterling cycle engine with one side in the shade and one side in the sun work pretty darn well anyhow?
I suspect that it DOESN'T, in which case they'll need to bore a big hole to put the heat in via fluid transferring to lunar dirt.
...after the rovers and the problems with keeping their solar panels cleared of dust...
If the panel isn't moving around, dust shouldn't be much of a problem on the moon. Although I've never visited, I understand that dust storms there are pretty infrequent.
That said, the long nights could be a real issue unless you're shipping a metric ass-load of batteries. Nuclear seems pretty reasonable.
But with all that He3, fusion should be just fine. Surely we'll have the kinks ironed out if we give ourselves 5-10 years, right? Or at least we can promise that we will so that we can secure funding?
He's getting rather old, but he's a good mouse.
Wake me when I can buy me a Ford Nucleon. 5000 miles on a single fueling. Take that, Tesla Motors!
http://twitter.com/OLDTELEGRAM
The 50's promise of a reactor in your basement to power those nifty gadgets are finally here!
I'm going to celebrate with some burgers in non-degradable styrofoam containers while driving my three ton car (with wings!) down a twenty lane highway.
Thank you Gernsback! *shudder*
Break the sound barrier - bring the noise.
...unless you're ok with only breathing during the day...
I don't know about you, but I SLEEP during the night. Sheesh, this isn't rocket surgery.
-- i am jack's amusing sig file
Ah, the articles says they'll have 1080 square feet of cooling. I'm not sure whether that says the vacuum stinks at cooling or not.
How much would be needed in air?
Yes, because, you know, we're going to have to drop atom bombs on those moon Nazis.
Of course, our other option is pelting them with hippies. Apparently, you're volunteering for that choice.
Mr. Hu is not a ninja.
Why would you send the reactor up *activated*? The only part of the reactor that's really of any concern is the fuel - enriched uranium. So, maybe the answer is to send the uranium up in little bits, so that even if it *did* blow up, there's such a small amount of non-reacted fuel (I might be wrong, but if I understand the nuclear fuel cycle, it shouldn't be very dangerous if it hasn't been reacted yet, and there's not a sufficient quantity to start a reaction?)
Can someone who knows more comment on whether I'm right or not? My understanding is that small quantities of unreacted uranium scattered in the atmosphere would pose essentially zero risk to life on earth?
If so, then you only assemble the reactor, insert the fuel, and initiate fission once it reaches the moon, at which point, who cares? I'm sure, having little atmosphere and no magnetic field to protect it, the moon must be subjected to a heck of a lot of radiation all the time, anyhow, no?
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
Thorium reactors don't make plutonium. No need for a light water or breeder reactor for it. I'm told that the fission byproducts are an order of magnitude safer as well, but I haven't seen the math for it yet.
Understanding the scope of the problem is the first step on the path to true panic.
think Solar panels
Your right in that
IAMAS (I'm not a Scientist)
wouldn't Solar Panels require
They've always struct me
a nuclear power planet
you would with Nuclear
lack there of
do you really think Uranium
Congratulations; you are a proud product of the AMERICAN PUBLIC SCHOOL SYSTEM!
BUT NO!! LET'S START FROM SCRATCH, BREAK THE BUDGET RE-DESIGNING THE WHEEL AND TAKE TWENTY FIVE YEARS TO GET THERE INSTEAD OF THE TEN IT TOOK US IN THE 60'S
We try to be a bit more careful with our astronauts these days, few applicants are test pilots any more, we like getting people back safely. There is no cold war or space race driving us to take risks to achieve goals. When we lose people and equipment, we now take sufficient time to understand what went wrong and how to fix it. And the budget hasn't been broken so much as drasticly slashed by people who have no concept of the benefit of space exploration.
Ignorance is Bliss -- And the Opposite is True -- Genius is Madness
Chances are, it'll already be on the moon and working before astronauts even get there. This is not the first nuclear-based energy source NASA has launched.
Not a typewriter
metric ass-load = about .85 of a fuck-ton.
How much does it cost to get .85 of a fuck-ton into low earth orbit? How much to get it onto a lunar trajectory?
I want peace on earth and goodwill toward man.
We are the United States Government! We don't do that sort of thing.
"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?
Well, in the poster's defense, if the sun literally "runs out" we have a slightly larger issue than our solar panels not working.
Nuclear power is NEVER a viable solution to ANY problem for the simple reason that the knowledge to create nuclear power is the knowledge to make nuclear weapons. For the simpler people in the crowd, NUCLEAR POWER EQUALS NUCLEAR WEAPONS. There is NO SUCH THING as a "peaceful" nuclear program. All nuclear material can and will be weaponized. For this reason alone nuclear power must be forever abolished and forgotten.
Bring on the U.N. sanctions. No one sell pocket protectors to NASA. They might be used for nefarious purposes.
How many Libraries of Congress is .85 of a fuck-ton?
Realistically, how much would it cost to get Congress onto a rocket bound for Sol?
"Lack of speed can be overcome. In the worst case by patience." --Znork
On an outpost that is hopefully* going to be permanently manned, 8 years seems a little short sighted. And if we're honest with ourselves, even those 8 years are not a realistic estimate. Consider that this thing has lots of movable parts and a very volatile coolant system all of which needs to withstand the extraordinary stress of launch and landing.
Consider RTGs on the other hand. They have no moving parts, a much longer lifespan, and a very well known failure mode (continuous degradation of the fission core and thermoelectric elements). While they do degrade considerably over several decades, they do not ever need maintenance and they don't fail suddenly like this very expensive and complex reactor will. Of course 40kW is an energy budget that could only be satisfied by several of these modules, but on the plus side this would promote a decentralized power architecture for the presumed offworld base. The reactor behemoth on the other hand will just fail spectacularly one day (probably after a long series of notorious problems that started on launch day) and Earth will need to ship a fucking big replacement package all the way up there while the Mars ground crew sits in the dark and with minimal life support, taking very shallow breaths.
* the reason I use that word here is because we probably will have just one phenomenally expensive mission that lasts a few weeks at the outset and after that we won't ever go there again. If the Moon mission era is any indication.
Could get difficult, politicians are extremely dense.
Justice is the sheep getting arrested while an impartial judge declares the vote void.
Okay, can someone tell me if I'm full of it or if this is a good idea?
The big 'excuse' of why we don't want a reactor in space is because the rocket might blow up and it'll cause cancer..
Why not use a large 'gun' (rail/coil/whatever) to launch the fuel into orbit instead of rockets?! Unlike a rocket which may fail anytime during it's ascent, a ballistic projectile is pretty much fool proof as long as the initial launch works properly and it doesn't hit anything.
But the best part is, I'm pretty sure nuclear fuel can't be damaged by the high G forces of launch so unlike astronauts or complex instruments we don't have to worry about excessive acceleration damaging the payload.
And if you want to get really crazy, if the launcher was electrically powered by a nuclear breeder reactor, you could manufacture the fuel on site instead of having to transport it.
And for the final thought, what if you build a gun like this for EVERY reactor? But instead of putting it into orbit make it powerful enough to launch it into the sun or out of the solar system, or into Jupiter. No more worrying about how to bury used nuclear fuel....
I think Parent poster is correct. You see, when the sun dips behind the horizon it has not actually gone out. It is very much unlike the lightbulb in your refrigerator, which turns on when the door is open, and off when it is closed. The sun is actually on the entire time, it just happens to be on the other side of the planet from where you are. We call that night. At any given point in time there are places on the planet that are in daylight, and places that are in night.
Where the parent fails is in leaving ambiguous the location of the solar panels. If they reside on the planet then they will only periodically provide power. But that is an implementation detail, and to conclude that parent is wrong with 100% confidence means that you would have to clarify a lot of these details either through assumption or by getting more information out of the parent poster.
You may also be confused by the fact that the sun will die. But you must understand that this will not happen for many millions of years, which in terms of human population and energy needs has been already accepted as "forever" by international bodies and consortia concerned with sustainable practices relative to human societies on earth.
Capital letters were an invention of Satan after he was thrown off the Anunaki space ship. He gave the first capital letter he invented, the letter L, to the Australian Aborigines who used it to hunt animals and wage war with each other. It is no coincidence that Viking battle axes are in the shape of the letter T and the Nazi Swastika uses 4 L's. I realized this while watching Sesame Street and having a nice glass of distilled water and pure grain alcohol. All those capital letters are shown by - wait for it - Monsters! It's all so very clear to me now! We must now take our capital letter to the moon so we can make an end of them and the moon-dwelling Nazis for all time!
Similar to the upcoming US election results
Weight is the main factor in the number of things that can go up in a rocket.
Nuclear is inherently a big win, in terms of Available Enthalpy (if scared, just read: Power) versus weight. Chemical reactions can yield 13 megajoules per kilogram. Nuclear fission can get you 82 million megajoules per kilogram. In terms of possible exhaust velocity, you can get 4.5 km/s out of chemical propellants, but a potential 12,800 km/s out of nuclear. Fusion is even better with 347 million MJ/kg of useful energy. But only using present day technology, beamed power sources can match anything out there in the theoretical realm. We'd only need to launch mirrors and reflectors and leave the heavy power generation on the ground. It wouldn't be easy, but the basic physics is very favorable -- tons of equipment could just sit on the ground instead of needing to be accelerated to high speed. (Sources, Zubrin's _Entering Space_)
Somebody doesn't seem to have done the math here. 2.3 kW of power, assuming ~1100 W/m^2 insolation, a 30% conversion efficiency, gives something like an array of solar panels less than 9 ft by 9ft (2.7 m^2). Does the article discuss how much the reactor plus the engine might weigh? I have a hard time believing its lighter than a solar array (unless they intend to launch it cold and bury it on site to shield people from the radiation).
Note any lunar sites are likely to be in places where there is a mixture of sun/shade and where long term oxygen/water production is likely to be handled on-site (so they are likely to have gas storage and/or electrolysis capabilities) for energy storage during any dark periods.
Mars is a different problem where planetary rotation and reduced insolation (esp. during dust storms) may come into play. But given the increased abilities one can expect from semi-intelligent robots over the next 10-20 years we have no business sending fragile humans on risky missions to Mars anyway. The only humans who should be going to Mars are those who can afford to pay for the trip themselves and stupid enough to want to take the risks involved in doing so. At the risk of being flamed -- you might wish to keep in mind precisely *who* came up with the humans should visit Mars plan (ignoring the bright people who might have been involved who presumably have vested interests in human space exploration) [1].
1. And don't give me the "humans need a refuge site" song and dance. Give me a cost comparison per person study between a Mars colony and self-sustaining terrestrial sub-surface ocean/land colonies. Anything that represents a significant threat in the near future (millions of years) to sub-surface colonies on Earth probably represents a threat on the moon or Mars as well.
Why don't we just ask the aliens that are already established on the moon what they use for a power source?
"I'm just here to regulate funkiness."
If the American public will accept the safety assurances of NASA, then the Russians and the Chinese are going to raise HELL about the idea of having nuclear energy in space.
Um, the Russians have actually already launched quite a few nuclear reactors (not just RTGs, although they've launched plenty of those too):
http://en.wikipedia.org/wiki/TOPAZ_nuclear_reactor
http://en.wikipedia.org/wiki/Category:Nuclear_power_in_space
Heck, in the 1970s one of the Russian reactors disintegrated over Canada, and the Canadians billed Russia a few million dollars in cleanup costs:
http://en.wikipedia.org/wiki/Cosmos_954
Not so much speed as efficiency, VASIMR is a great old technology because it has a high specific impulse, basically acceleration per unit fuel, not because it can go from 0-60 in 4 seconds flat (which it could).
Unfortunately, 40kW is hardly sufficient for a VASIMR system, which requires many MW of power to operate at high SI. For example, all together the ISS right now produces something like 130kW of power with solar, meaning it will have to charge a battery to be able to use the VASIMR they intend to install on it sometime around 2012.
When you're afraid to download music illegally in your own home, then the terrorists have won!
I would certainly not want to touch a Uranium rod with my bare hands. It is not the radioactivity you need to worry about but the toxicity of the metal.
14 days without light IS the problem. Assuming the 40kW power of the nuclear reactor and calculating the equivalent requirements: If they use a 160V DC bus, like on ISS, then they'd need 84,000 Amp-hours worth of batteries. To give you an idea of how big that is (and recalculating for a specific battery type), using Nickel Hydrogen batteries (also like the ISS) which are 75 Wh/kg, you'd need 179,200kg = 394,240lb = 197 tons of batteries.
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.
Thorium reactors don't make plutonium. No need for a light water or breeder reactor for it. I'm told that the fission byproducts are an order of magnitude safer as well, but I haven't seen the math for it yet.
Please check Kirk Sorensen's Google Talk about thorium nuclear reactors. And here are the actual slides used in the presentation.
From the Introduction and Basic Principles of thorium based reactors on Kirk's blog: A liquid-fluoride thorium reactor operating only on thorium and using a "start charge" of pure U-233 will produce almost no transuranic isotopes. This is because neutron capture in U-233 (which occurs about 10% of the time) will produce U-234, which will further absorb another neutron to produce U-235, which is fissile. U-235 will fission about 85% of the time in a thermal-neutron spectrum, and when it doesn't it will produce U-236. U-236 will further absorb another neutron to produce Np-237, which will be removed by the fluorination system. But the production rate of Np-237 will be exceedingly low because of all the fission "off-ramps" in its production.
-k
Because we have VASMIR coming. Combine that with a nice nuclear reactor and we are looking at some good speeds.
The 2.3kW of this sterling engine doesnt speak to that promise. The 40kW they hope to have a ground system producing doesnt instill much confidenc either. ISS produces around 130kW, via a colossal truss-work of solar panels. These are all far short of the 400kW power needed for the target baseline VASIMR engine, and well short of the multi MW power levels VASIMR really is designed for.
Nuclear power generates heat. Heat differential is then used to drive turbines. In space, you may be able to make heat, but what is there for the other end of this power generation equation; where does the cool body of mass come from, the essential other integral to power generation?
VASIMR itself, at high ISP's, is generating 10 megakelvin plasma. That itself has cooling challenges.
Right now, I dont see how these ideas are practical.
You might kick some up, but unless the stuff is given a decent ballistic velocity it won't go anywhere. Can't exactly hang around in the air, right?
Actually, you couldn't be more wrong.
The dust particles get a charge off the solar wind and sunlight itself, then repel one another. Result: Dust hanging about in the air (well, mainly lack of air actually).
Moved to http://soylentnews.org/. You are invited to join us too!
Okay, how?
During the day, lift heavy rocks upward. During the night, lower them.
Dewey, what part of this looks like authorities should be involved?