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Power Mars Moon NASA Space

NASA Developing Nuclear Reactor For Moon and Mars 424

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."
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NASA Developing Nuclear Reactor For Moon and Mars

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  • Cheap? (Score:2, Insightful)

    by Garridan ( 597129 )

    "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".

    • Re:Cheap? (Score:5, Insightful)

      by QuantumRiff ( 120817 ) on Monday August 17, 2009 @12:15PM (#29094457)
      When your talking about space, spending a fortune on exotic, super lightweight materials will save you many times more than that cost in launches. Weight is the main factor in the number of things that can go up in a rocket. I think I remember hearing someone mention in the ballpark of $25,000 per pound. So while you look at Cheap as the total cost, they look at it a bit differently.
      • 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 ou

  • by Killer Orca ( 1373645 ) on Monday August 17, 2009 @11:33AM (#29093655)
    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.
  • by morgan_greywolf ( 835522 ) on Monday August 17, 2009 @11:34AM (#29093671) Homepage Journal

    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.....

    • by Brett Buck ( 811747 ) on Monday August 17, 2009 @11:42AM (#29093875)

      And if a meteor *does* strike the reactor, we are going to contaminate the Moon with radioactivity? More than being exposed to an unshielded fusion reactor for 4.5 billion years?

              Brett

      • My thoughts exactly. The moon is already blasted with radiation all the time. There's no atmosphere, and no electromagnetic field like we have on earth. Having a nuclear meltdown on the moon wouldn't even be noticable. I guess there could be some concern over the nuclear fuel exploding on takeoff, but, I think proper precautions could be taken such that even if the launch rocket did blow up, that it wouldn't contaminate the atmosphere.
      • by infinite9 ( 319274 ) on Monday August 17, 2009 @12:16PM (#29094505)

        Lol, sounds like another opportunity! Head out to the next anti-nuclear rally and get people to sign a petition to shut down this unshielded fusion reactor. It's exposing us to several types of radiation every day, even as we speak! It causes severe burns on many people every day! Many species won't come out of their burrows because of it! While you're at it, you can ask them about their opinion of dihydrogen-monoxide.

      • by WindBourne ( 631190 ) on Monday August 17, 2009 @12:44PM (#29094915) Journal
        Assume that a 100 MW reactor blew up and spread around the moon (and it would spread). It would contribute less radiation to the lunar surface each day than what the sun does each hour. So, what is the problem?
    • by h4rr4r ( 612664 ) on Monday August 17, 2009 @11:48AM (#29093975)

      The problem would be what exactly?
      The impact to the wildlife on the moon?

  • by Anonymous Coward on Monday August 17, 2009 @11:34AM (#29093673)

    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.

    • Mod parent up please (Score:5, Informative)

      by Kupfernigk ( 1190345 ) on Monday August 17, 2009 @11:52AM (#29094039)
      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.
  • by istartedi ( 132515 ) on Monday August 17, 2009 @11:34AM (#29093681) Journal

    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.

    • by Shivetya ( 243324 ) on Monday August 17, 2009 @11:51AM (#29094023) Homepage Journal

      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.

    • by lgw ( 121541 ) on Monday August 17, 2009 @12:10PM (#29094351) Journal

      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 [wikipedia.org] 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".

      • by Brett Buck ( 811747 ) on Monday August 17, 2009 @12:46PM (#29094963)

        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

        • by greyhueofdoubt ( 1159527 ) on Monday August 17, 2009 @09:11PM (#29100161) Homepage Journal

          Hydrazine is a little bit more toxic than you make it out to be.

          The F-16's epu uses hydrazine (about 80 lbs of it are in a tank aft of the cockpit). During epu tests, everyone gets upwind (regulation). Our hydrazine response team wear full-protection SCBA spacesuits to clean it up. If a person is exposed, they get regular blood tests for the rest of their lives.

          I work closely with a few people who have been exposed, and they are reminded with every passing hour that they cannot breath as well or feel as well. You can say, "yeah, comes with the territory," but it's pretty heartbreaking when you know that these guys have beautiful kids who are probably going to lose their dads within 10 years...

          -b

  • For some reason, I'm not too concerned with having a nuclear reactor on the Moon or on Mars. Sure, there are risks in launching it, but it's probably not going to be operating while it's being launched, so I'm not especially worried about that either.

    Besides, in 90 years, when they've built up a huge moonbase and a large stockpile of spent nuclear material, it can explode and send the moon hurtling out of the solar system! It'll be Space: 19992099!
  • Engine (Score:5, Informative)

    by Manfred Maccx ( 1365933 ) on Monday August 17, 2009 @11:36AM (#29093727)
    It's a Stirling Engine....not Sterling.
  • Sterling engine? (Score:5, Informative)

    by __aagctu1952 ( 768423 ) on Monday August 17, 2009 @11:37AM (#29093737)

    An engine made out of silver [wikipedia.org]? Or just a generally excellent [merriam-webster.com] one? Ah, a Stirling engine [wikipedia.org].

    More quality editing from Slashdot...

  • by Anonymous Coward

    Stirling from the name of inventor - Dr. Robert Stirling.

  • by ameline ( 771895 ) <ian.amelineNO@SPAMgmail.com> on Monday August 17, 2009 @11:38AM (#29093761) Homepage Journal

    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)?

    • you can do a lot with 20amps.... whats your point?
    • by Graff ( 532189 ) on Monday August 17, 2009 @11:58AM (#29094141)

      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.

      • by vlm ( 69642 ) on Monday August 17, 2009 @12:19PM (#29094543)

        40 kW is approximately 17 outlets that can handle 20 A at 115 V.

        So, if all they ran were grow lights, that would be about 30 grow lights? I'm thinking that is not enough to grow the food for even one person during the lunar night. Assuming all you did with your electricity was grow some chow. I think one grow light's worth of plants is not enough for one persons daily food intake, and you're not going to grow a crop in rotation 30 days.

        True, you've got plenty of light during the long lunar day, maybe it would be possible to do reduced light for 8 hours to 3 plants, but thats probably going to screw up the growth cycle of ... anything?

        Hmm. So if you electrolyze water at a rate of 40 kW, and the average human needs about 3 Kg a day (rounded up) how many people can breathe? Of course you also need life support to freeze the CO2 out of the atmosphere, and some way to turn that CO2 into C and O2 or into plant matter.

        No, I'm thinking you need well over 40 KW per person for a sustainable moon colony.

        • Re: (Score:3, Informative)

          by WindBourne ( 631190 )
          So, if all they ran were grow lights, that would be about 30 grow lights?
          It would be silly to use this for loads of growlights, when you have places on the moon where you can obtain near total sunlight. You will have to raise some pipes up and redirect the sun down, but I am certain that a number of spots on the poles can be found to do that with.
        • by nasor ( 690345 ) on Monday August 17, 2009 @05:18PM (#29098367)
          The linked article doesn't really communicate the selling point, which is that these reactors are very small; the whole thing fits in a roughly 1 x 2 meter package (larger when you deploy the fold-radiators). It's true that one wouldn't be enough to power a large base, but NASA isn't planning anything like a base with a greenhouse for growing food - these things are basically meant to provide power for the astronaut's lander/trailer when it's dark outside. They just need to run the life support systems and radios.
      • So the question is, what do they do with the test version when they are done? That would power my house, and my neighbors.. or my house, with a conversion to all electric heat...
    • great. so, when can i put this in my back yard?
    • Then you pair it with low draw systems and a large capacitor.

      That's just their test rig anyway - the model. TFA States:

      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.

      That oughta be enough.

  • by tjstork ( 137384 ) <todd.bandrowskyNO@SPAMgmail.com> on Monday August 17, 2009 @11:40AM (#29093803) Homepage Journal

    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.

  • by MozeeToby ( 1163751 ) on Monday August 17, 2009 @11:43AM (#29093883)

    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.

  • Maybe NASA should invest a bit more down here in Earth, buying to the mad Dr. Browm a bunch of old Deloreans to see if somewhat can get a small (Mr.) Fussion reactor. Or wait just 6 years,
  • by mykepredko ( 40154 ) on Monday August 17, 2009 @11:49AM (#29093993) Homepage

    When I first saw this, I thought it was for powering VASIMR [adastrarocket.com] 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

  • by kawabago ( 551139 ) on Monday August 17, 2009 @12:01PM (#29094211)
    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.
  • by wonkavader ( 605434 ) on Monday August 17, 2009 @12:05PM (#29094287)

    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.

    • 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?

    • by vlm ( 69642 ) on Monday August 17, 2009 @12:34PM (#29094769)

      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?

      Yeah, it does. An infinitely large radiator protected from the sun and from the surface would cool to around 2.7 degrees kelvin, pretty chilly. When you understand why it won't cool any further, then you'll know a lot more than you need for this engineering problem, although it is interesting. There are engineering limitations where adding another kilometer of radiator tubing to drop from 4K to 3K just isn't worth the cost of tubing, and/or the power required to pump the refrigerant thru the tubes. Radiation power increases as a pretty high power of temperature.

      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?

      Look up the rotation period of the moon. Very roughly, Dark for 2 weeks, Light for 2 weeks. Unless you make a engine thats about 1/2 the circumference of the moon (or, just the diameter, if you were REALLY hard core). Which is not totally out of the question, although it would be a heck of an amazing civil engineering project.

    • Re: (Score:3, Informative)

      by Nyeerrmm ( 940927 )

      A heat source on earth is cooled by conduction (a pot transferring heat to the surface its sitting on), convection (air moving over the surface and carrying away heat), and radiation (direct transmission of energy via photons). In the "icy vacuum of space" you get no conduction or convection, so you're limited to radiation as a method of dispensing of heat. If you're on the moon you can conduct a lot back into the ground as you suggest as well.

      However, the black cold of space is a pretty good source to ra

    • Re: (Score:3, Interesting)

      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?

      Heat is only transferred through conduction or radiation, with radiation being the most efficient, convection is a movement of heated materials, but the heat itself is only ever conducted or radiated away.

      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.

      The key to the operation of any type of thermo-electric device is temprature differential, the greater the difference in temperature from one end to the other, the greater the power output. Sitting in the sun on earth, there would be a maximum of about 20-30 degrees difference in the most ideal situatio

  • Yawn. (Score:5, Insightful)

    by FlyingSquidStudios ( 1031284 ) on Monday August 17, 2009 @12:08PM (#29094327)
    Wake me when I can buy me a Ford Nucleon [wikipedia.org]. 5000 miles on a single fueling. Take that, Tesla Motors!
  • by thasmudyan ( 460603 ) <thasmudyan@opREDHATenfu.com minus distro> on Monday August 17, 2009 @01:46PM (#29095805)

    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.

  • 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.

    • 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).

      The article is reporting on a test of a heat transfer and power production prototype, not a proposal for an actual reactor for moon deployment, with operational specifics. However, launching the reactor cold, and using cheap local materials for shielding, is exactly how such proposed schemes usually work.

      But a key factor you are overlooking is how to provide continuous power. A solar system on the moon gets no light for 14 days at a stretch. This requires 775 kWH of power storage. Battery and flywheel techn

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