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A Bomb in Space

  1. Mar 13, 2004 #1
    I am wondering, if a bomb exploded in the "vacuum" of space, without an atmosphere to cause a pressure wave, what would be the destructive area of the bomb, or would there be any?
  2. jcsd
  3. Mar 13, 2004 #2
    The energy of an explosion in vacuum would be distributed over a greater volume, unrestricted by an atmosphere. In space the supersonic solid debris, light, gas and heat from the blast would constitute by far the majority of this resultant energy.
  4. Mar 14, 2004 #3


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    You wouldn't have a pressure wave, but you would get impacted by tons of high energy microscopic particles.

    Damage would probably be higher in close proximity merely due to the increased particle flux, but I'd guess the damage would not be as great as it would be in an atmosphere.
  5. Mar 14, 2004 #4


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    "Destructive area"? In vacuum what would there be to destroy?
  6. Mar 14, 2004 #5
    It should be obvious the he meant "potentially destructive area" and is how I interpreted his question regardless of the actual words used.
  7. Mar 14, 2004 #6
    Perhaps he intended to say something more like "cross-section."
  8. Mar 15, 2004 #7
    Got you, timejim! You're a secret agent of the Pentagon on research for the future "galaxy wars" weapons system, aren't ya? Hahaa! If you can get me a job in that project I won't tell anybody, ok?
  9. Mar 15, 2004 #8
    As an aside to this question, whenever I see an explosion in space on TV it always has a taurus carrying the energy away. Does this really happen and if so what defines its plane?
  10. Mar 15, 2004 #9


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    I think you mean 'torus'; cool huh? It sure happens in movies; I guess the plane is defined by the special effects team.

    Seriously, as far as we know, the preferred 'plane' for cosmic explosions - e.g. gamma ray bursts and supernovae (at least some kinds) is the rotational axis of the poor star - the burst goes through the poles.

    For magnetars - which may be responsible for the short duration GRBs - I guess the preferred plane of emission would be related to the magnetic field in some way.

    [Edit: added link to a magnetar website]
    Last edited: Mar 15, 2004
  11. Mar 15, 2004 #10
    It does look cool, look better with a big bull rising out of the flames though! :wink:

    So they do exist then. I take it they’re made of whatever’s left of whatever exploded? Does the force of the blast travel primarily in this plane?

    How about if a nuclear or chemical explosive where to be let of in space?
  12. Mar 15, 2004 #11
    I would think that the destructive pattern would diminish as an inverse square to the distance from the blast.
  13. Mar 15, 2004 #12


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    AFAIK, the main difference between an explosion 'in space' and one in the atmosphere is that for the latter the air slows the matter accelerated by the explosion (gas, solid fragments). If the 'bomb' is designed to go off with preferred directions (e.g. a 'shaped' explosive), it'll do the same 'in space'. On Earth, the thing which really makes a difference is, well, the Earth!
  14. Mar 16, 2004 #13
    a nuke in space would be an omnidirectional blast. there would be no mushroom cloud, it would be exspanding in all directions, for far greater distance than it would on earth, but, there would also be no shockwave. greatly reducing the potential damage. also, the only damage area would be where the fireball is.
  15. Mar 16, 2004 #14

    In a space nuke explosion...I'd be more worried about the neutron and X-ray emissions.
  16. Mar 16, 2004 #15
    Fire requires fuel, oxygen, heat. I don't think there would be a fireball. It would be interesting to know what would happen.

    I imagine that The debris would shred through anything close to the blast, but it would be silent and as you said no shockwave.
  17. Mar 16, 2004 #16
    Remember the epoch of decoupling and the resultant "fireball."
  18. Mar 16, 2004 #17


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    Let's say we have 10 kg of H, maybe mixed deuterium and tritium. we compress it and heat it (all in deep space, without any other 'material' intervention) and much of it fuses to He (etc).

    Now we've got ~10 kg of H and He at a temperature of (say) 100 million degrees*, surrounded by a vacuum more perfect than we can create on Earth.

    What happens?

    We can run the same thought experiment, with a Chinese firecracker, a hand grenade, a mortar shell, a 2000 pound bomb, (but not a MOAB).

    *Anyone have a reference to the temperature of a pure H-fusion 'bomb'? It'd likely also be ~the temperature at which ITER (etc) would yield net energy.

    [Edit: added * note]
    Last edited: Mar 17, 2004
  19. Mar 17, 2004 #18
    The oxygen used for combustion in many gunpowders is contained within the powder itself, in the nitrates. (potassium nitrate, sodium nitrate) -Mike
  20. Mar 17, 2004 #19
    not all "fire" needs oxygen. dont forget its a nuke we're talking about. the "fireball" is pure released energy. the same way the sun is "on fire".
  21. Mar 17, 2004 #20
    Read first post. Where says nuke?
    Last edited by a moderator: Mar 17, 2004
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