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Can a nuclear explosion be vectored?

  1. Apr 27, 2010 #1
    Is it possible to direct a nuclear explosion in a particular direction? The idea of a "Nuke Cannon" seems humorously over the top and impractical, but just for arguments sake, could it be done?
  2. jcsd
  3. Apr 27, 2010 #2
  4. Apr 27, 2010 #3
    That's interesting, but as it says "shrouded in mystery". I was under the impression that no physically plausible material could withstand the heat and pressures of a point blank nuclear detonation.

    I also wonder if a device like that was actually fired projecting an arc of destruction across a landscape far into the distance, what should we expect the mushroom cloud to look like?
  5. Apr 28, 2010 #4
    It is largely a matter of perspective or proportion. Even ordinary artillery and shaped charges cause considerable excitement in all directions apart from where they are shooting. It is however possible to do sufficient transient steering of part of a nuclear explosion to achieve specific objectives, sometimes directly, sometimes indirectly. For example one can employ some of the radiation of a Pu nuke to detonate a fusion weapon. The diffraction only has to work for a few microseconds, and well-designed inertial masses can suffice for that.

    There are plenty of options. For example, suppose you want to deflect the path of an asteroid or comet gently. Explode a nuke near the surface, with a tamping mass on the other side of your bomb to concentrate as much of the radiation as possible on the target. First the radiation arrives and ablates some of the surface, causing intense, but gently dispersed, reaction forces on the target. Meanwhile, the tamping mass also volatilises, some of its vapours and some of its EM radiation subsequently adding a bit to the propulsion of the target.

    Everywhere else in the neighbourhood is a healthy place not to be, but the effectiveness of the exercise still depends on just how well it is directed. Personally I am not terribly keen on nukes for NEO steering, but I reckon it could be the basis for the best strategy in an emergency. After all, what could the harm of a megaton in space be, compared with a teraton impact on Earth?

    Just remember to blink!

    Last edited: Apr 28, 2010
  6. May 16, 2012 #5
    Yes, this is how they use a fission primary to create the pressure and temperature necessary for a fission-fusion (thermonuclear) weapon. In practice, the blast is focused ....but only for milliseconds, as the containment structure is eliminated almost instantly. There is no known method of shaping a nuclear weapon. Technically, you could put a mountain next to your explosion to make it reflect away from the mountain in a general direction...... but that's not really in scope.
  7. May 17, 2012 #6
    You stopped short at mountain. Using the earth itself is even more effective, and indeed an underground shaft used as a cannon barrel has been termed a "thunder well" (although it's hard to find good references for this)


    I have even watched a show on how to fight an alien invasion, and an interesting idea was using a large array of these "thunderwells" to attack a mother ship orbiting the earth. Essentially shoot hundreds/ thousands of heavy metal plates at ridiculous speed into the path of the spaceship. At the very least it would be a spectacular last-ditch effort of the human race to perhaps make the invaders look for an easier target....and a slight justification for our war-like, self-destructive nature.

    Of course, whether this idea would work at all (even on paper) is a whole different matter.
    Last edited: May 17, 2012
  8. May 18, 2012 #7
  9. May 21, 2012 #8
    Just to clarify...this not a nuclear cannon. This is a conventional chemical cannon with a nuclear warhead in the "shell". I think the OP was referring to using a nuclear blast to fire the projectile. Lsos has the correct idea and a interesting link referencing "thunderwells".
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