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Peacful Nuclear Explosions: Orion Project?

  1. Aug 6, 2011 #1
    I've been looking into some of the various treaties regarding the use of nuclear explosions, and I'm having trouble figuring out some of the gray zones; The United States and Russia have both signed treaties http://en.wikipedia.org/wiki/Comprehensive_Nuclear-Test-Ban_Treaty" [Broken]

    So my question is whether or not http://en.wikipedia.org/wiki/Project_Orion_%28nuclear_propulsion%29" [Broken] would be considered peaceful? The limited test ban treaty bans "nuclear testing" in atmosphere and in space, but so far as I can tell there is no treaty either expressly allowing or banning such a practice. Are there major engineering challenges that simply can't be overcome, or is the obstacle to such a program political? The wiki article on the orion project states that the "partial test ban treaty is generally acknowledged to have ended the program," so does that mean this use falls under bans included in that treaty?

    On an engineering note, how does nuclear pulse propulsion compare to, say, a nuclear rocket, or other fission reactor powered designs?
    Last edited by a moderator: May 5, 2017
  2. jcsd
  3. Aug 7, 2011 #2
    Try to find a copy of "Project Orion: The True Story of the Atomic Spaceship" by George Dyson.

    Wow, I just looked on Amazon and the price of this book is really high ($60+ used). Anyone know why that would be? There's one for $20 on ebay. I guess it's OP, but still...
  4. Aug 7, 2011 #3


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    Such a craft would have to be enormous and therefore expensive.
  5. Aug 7, 2011 #4


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    The wiki article on http://en.wikipedia.org/wiki/Project_Orion_(nuclear_propulsion)" [Broken] is very good. Points out that yes the craft must be fairly massive but not necessarily voluminous .

    Freeman Dyson studied the problem in depth, producing the 1968 paper "Interstellar Transport". He comes up with a ship to go the several light years to a near star, pricing it out from 1/10 to one full year of GNP, depending on design type.
    Last edited by a moderator: May 5, 2017
  6. Aug 8, 2011 #5
    Launching it from the earth is a problem though, because essentially all the fission products from the launch are then released into atmosphere. And the craft is too heavy for lifting using conventional rockets.

    The reason for ban of atmospheric nuclear testing was the pollution, not so much the weapon development. Atmospheric nuclear testing was banned in 1963 or so. USA conducted the last underground nuclear testing sometime around 1992 , which suggests that the reason for termination of nuke testing in general was the end of cold war.
    To launch Orion vehicle from each you'd have to violate the old agreement from 1963, and it won't matter in the slightest that it is 'peaceful' use 'cause it pollutes the same.
    Last edited: Aug 8, 2011
  7. Aug 8, 2011 #6


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    Launched in pieces and assembled in orbit it would not be too heavy. The International Space Station, for instance has a mass of ~417 MT.

    I think the relevant treaty issue would be not in launching a bomb powered craft - we really don't need or want to do that. Rather the issue would be in getting leave to launch the nuclear explosives into orbit to use later on a planetary (or stellar) mission. So while I might be persuaded to have the US build such a craft, I don't want other nation states like China orbiting nukes to ostensibly launch an Orion to Mars.
  8. Aug 8, 2011 #7
    FOBs are a boogaboo. A theoretical solution to a theoretical problem that would have theoretically been put by Reagan's utterly theoretical missile defense system. It costs fuel to maintain any kind of useful (read: low) orbit, plus any semi-competent adversary can kinetic-kill them while they leisurely float along, parked at Lagrange or whereever.

    A more cogent critique, imo, is the one wrt reliability of launch vehicles that would put the nukes in orbit. Anything less than 100% is probably unacceptable, yet 100% cannot be attained even in theory.

    Now, if antimatter were less costly to produce and store...
  9. Aug 8, 2011 #8


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    If that were the case then nuclear weapons would never have be allowed on atmospheric aircraft readiness missions or even transport.
  10. Aug 8, 2011 #9
    Readiness missions have not been flown in what? Three-four decades? There are accidents and mishaps even with transport aircraft, which are arguably much more reliable than any rocket. But yes, I was exaggerating when I wrote "100%".
  11. Aug 8, 2011 #10
    The idea of just droping nukes out the back to push you foward seems ludicrously primitive. Only a fraction of the blast energy would push the craft fowrard. Nuclear energy is definately a viable option for space travel, and in my opinion the best, but bombs wont propel us. Rockets will.

    My 3 favorite ideas.

    When I was reading about the salt water rocket, talking about earth to orbit launches, one said it would be great for that. If you don't mind the launch site glowing blue for a million years.
  12. Aug 9, 2011 #11
    So overall what I'm gathering is that fallout is an issue in atmosphere, but far less of a concern in space. Does that mean that, say, a joint mission consisting of various nuclear arms bearing countries as well as the countries that worked on the ISS could come together and build something like this? Could the US and Russia both contribute weapons from their stockpiles almost as is? Also, any thoughts on reusing ICBM launch vehicles as a way to assemble such a craft in orbit?

    It seem primitive until you realize that our nuclear weapons have a much higher peak power output than any reactor can possibly obtain. You can launch however large of nukes you need out the back to give you whatever average power you desire, at much lower mass cost than a reactor. Plus if you need a really big nuke you can add a fusion stage of relatively easy to obtain fussionables and even a third fission stage of plain old U-238.

    I'd honestly be willing to stake my own hide that even if the rocket blew up there would be negligible fallout from the nuke(s), and the nuke absolutely would not detonate. Nuclear weapons are designed with the mentality that even having half of them be duds is preferable to having even one accidental or unauthorized release.

    Sure it would be expensive compared to a space shuttle or the like, but a Nimitz class aircraft carrier? How about a Boomer sub? A 400,000T spacecraft is on the same order of magnitude. Plus you could potentially recycle cold war weapon stockpiles and launch vehicles for much of the necessary mass. Put your WMD's to good use, you know?
  13. Aug 9, 2011 #12
    Stake your own hide, you say? Fine and dandy. Go terraform Mars and perform your experiment there. Not on MY planet.

  14. Aug 9, 2011 #13
    Hmm, so the conventional explosive is likely to go off in the event of catastrophic failure of the rocket... In that event I would recomend transporting the nuclear material to orbit separately in some blast proof configuration, transporting the conventional explosive as a bulk good(it's cheap, so less reliable rockets are required), and assembling both in orbit as needed.
    Last edited by a moderator: Apr 26, 2017
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