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Is A Nuclear Reactor A

  1. Jul 13, 2004 #1
    Is A Nuclear Reactor A......

    I am not sure if this is the right forum or not, I figure its about space stuff so it might be.

    My question is, could one safely use a nuclear reactor on a large-scale space station. Of course there is the issue of shielding, but since space stations have to be shielded against virtually all forms of radiation anyhow, adapting the shielding for a nuclear reactor would not be hard.

    My question is, would it work, and is it viable.
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  3. Jul 13, 2004 #2


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    I'm going to give you my opinion. Some day I read a newspaper article that talked about mars permanent ground station. This was a part of a sciencist thesis. It could be read how this station would keep on living on mars surface, with the help of a nuclear reactor and vehicles, and an oxygen generator. Well, now this sciencist (spanish by the way) is working at NASA.
    But to my surprise, the article (I don't know if the thesis as well) does not talk about HOW can human beings transport a nuclear reactor inside of a spaceship. I think it's too heavy for trying it with newadays technology. It is not only the reactor core, but heat exchangers, pupms, turbines, refrigeration systems, pipes, in order to produce some power there.

    I don't know exactly what is the shuttle thrust at liftoff, but surely that Soyuz rocket is not capable for transport it.
  4. Jul 13, 2004 #3
    I know nuclear thermoelectric generators have already been used on probes so I would think you could put it on other spacecraft. Its just that its dangerous having radioactive materials orbiting so close to Earth. If it fell into the atmosphere it could be devistating.
  5. Jul 13, 2004 #4


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    It is a huge engineering undertaking to have a useful and operational fission reactor in space. The energy is released as high speed neutrons. They are not an immediately useful form of energy. They are captured by water, which becomes steam and is used to make turbines rotate. We are not talking about just some uranium and a little machinery. We are talking about something that outweighs every bit of man-made stuff put into orbit combined I would bet - probably by more than an order of magnitude.

    Even so, it is more of an engineering challenge than a science challenge, and more of an economic challenge than an engineering challenge.
  6. Jul 13, 2004 #5
    Yes one could. In fact, NASA is building another part for the ISS with TWO nuclear reactors in it. It can supply energy for 160 years or more.
  7. Jul 13, 2004 #6


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    Yea, I keep thinking about Skylab. If it had a reactor onboard, we'd have had some real trouble! Before we do any such thing, I think we need to remind ourselves that what goes up must eventually come down.
  8. Jul 13, 2004 #7
    First off, I want to thank you all for you input, and any others that fallow this post.

    Most of you point out that while you could, the big problems would be getting it there, and what happens if it falls out of orbit.

    I don't have an answer for the getting it there part, but as for falling, most sattilites are in low, unstable orbits, the station I am talking about would be in a very high, and stable orbit.

    Check this site out, its the results of a Space Settlement Contest by Nasa, this is a previous winner, look at chapter 2.

    http://www.belmont.k12.ca.us/ralston/programs/itech/SpaceSettlement/Contest/Results/2004/winner/leda.html [Broken]
    Last edited by a moderator: May 1, 2017
  9. Jul 14, 2004 #8


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    Fission devices of all kinds are still banned from orbit by international treaty, I believe. Those reactors are almost certainly of the type that utilize radioactive decay, not fission.

  10. Jul 14, 2004 #9
    Radioactive decay is fission.
  11. Jul 14, 2004 #10
    I don't know about international treaty, but I do know that the U.S. has satallites in space that have nuclear reactors on them with weapons grade material on them. As well as russia and china are also supposed to have satillites with nuclear reactors on them....
  12. Jul 14, 2004 #11
    As far as I know, controlled fission reactors are completely legal in space. The Partial and Outer Space Test Ban Treaties stated that no nuclear weapons or explosions were permitted from the upper atmosphere and the heavens themselves.

    It sickens me to see so many "treaties" hampering human expansion. A trip with a system that utilizes small nuclear charges for propulsion could get a ship from the ground to anywhere in only a few weeks. Instead, the NASA plan involves making space stations and lunar bases and martian expeditions for hundreds of billions of dollars! With a so-called Orion nuclear pulse rocket, you could get to wherever you want in the solar system with a single ship. No three-stage titanic chemical rockets that require strict launch windows are needed, no huge sums of cash are required.

    Is a device you can activate and stop at will controlled? If so, Orion should not be limited by some pathetic little law blathered by buero-twits.

  13. Jul 15, 2004 #12


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    I was wrong :eek:

    It is only explosives that are banned. Several reactors have been put into orbit, including one by the US (now defunct).


    They seem to be incredibly low power, for a nuclear reactor. I did not know you could make them work at such low powers.

  14. Jul 15, 2004 #13
    I don't think that's correct. Read this link:


    Scroll to the bottom and read the section titled "Safety." From the link:

    Also, this PDF from NASA about the Cassini mission underscores the fact that RTGs aren't nuclear reactors:

    http://saturn.jpl.nasa.gov/spacecraft/safety/power.pdf [Broken]

    In short, the natural radioactive decay used in RTGs is not the same as the nuclear fission caused by chain reactions in a nuclear reactor.
    Last edited by a moderator: May 1, 2017
  15. Jul 15, 2004 #14
    Okay... That doesn't disprove what I said at all. Look here: http://dictionary.reference.com/search?q=fission

    "Splitting into framents" sounds a lot like "decaying." Wheather or not its emitting just a neutron, alpha particle, or into two equal new nuclei.

    Anyways its not really important.
    Last edited by a moderator: May 1, 2017
  16. Jul 15, 2004 #15
    Fission reactions work by the process of neutrons stimulating atomic nuclei. An RTG gives power by "dying" isotopes, which are already unstable. The isotopes' short lives generate a low amount of power, which is good for passive space probes in areas of low solar intensity. In either type of atomic power, radioactive decay is important: A neutron source is needed to split the atom.

  17. Jul 26, 2004 #16
    This is true but u must also keep in mind 'down' is relative with gravity.. down to me is up to the chinese and down for us may be sideways for ppl on Mars.. Down is the direction in which gravity is acting....
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