Re: russia_1.html

[Anonymous <anon@anon.efga.org>]

Peter Trei:
>The plutonium cores of thermonuclear devices have a limited shelf
>life - he claimed 6 years, which jibes with what I've heard from
>other open sources. Fission products build up in the cores which
>can poison a chain reaction. Thus all Pu based devices need to have
>the cores periodically removed and replaced with new ones, while the
>old ones have to go through a non-trivial reprocessing stage to
>remove the fission products.

Warm&ComfyMonger:
>Decay, rather than fission, I suppose.   I believe there's a treaty
>prohibiting nuclear weapons in space.  Not so surprising if they're
>inpractical - political points for nothing.

No.  Fission, not decay.  Pu239 decays into U235, which explodes just fine.

The problem is that background radiation (cosmic rays, etc) causes the Pu
to fission.  This sets off a chain reaction which fissions other Pu atoms.
If you have less than a critical mass, this will eventually burn itself
out, but it makes a mess of your core in the process.

As for space nukes, well, if you go stick something up in orbit where its
exposed to all sorts of radiation to destabilize the Pu... well you'll be
lucky if it doesn't melt down, much less last very long.  Furthermore,
there is all sorts of junk in low earth orbit, sooner or later something
is going to knock it out of orbit...

- NukeMonger