> Richard Plourde <rplourde@andesign.mv.com> wrote:
>
> > For example, in 1997 we have no control over a killer-asteroid.
> > If, on the other hand, we had continued developing
> > out-of-earth-orbit space craft in 1970, then very possibly we
> > would have control over such a killer asteroid.
> >
> Really? What if you stuff a (slightly modified?) space shuttle full of
> nuclear warheads and send it on a collision course with the asteroid so
> that it either gets blown to small, and relatively harmless bits, or
> changes direction so that the impact is avoided. That would
> probably do the trick...
Well, I think it is a bit harder than that. Blowing up asteroids
takes a lot of energy, and just a few megatons will not do it well.
And changing the direction needs a lot of impulse if you do it
just before impact. Essentially the problem is not our nuclear
capabilities but the fact that if we discover a killer asteroid,
it will likely be too late - even if we scramble and use all our
available shuttles (not intended to leave orbit, so they will
need strap-on propulsion) and spare warheads we will not be able
to change the trajectory enough. What we really need is a better
spacewatch program, and with a few years advance warning we
can easily put a impulse engine on the asteroid, turning a hit
into a near miss.
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