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Billy Brown <email@example.com> Wrote:
>I hereby challenge anyone to come up with a disaster, natural or
>artificial, that could reasonably be expected to render an advanced
>spacefaring species completely extinct.
No need to conjure up exotic stuff like Hypernova's or Gamma Ray Bursters, just a garden variety supernova would probably do the trick if it were close enough. Neutrino are normally harmless but the flux from one of these monsters would be so incredibly enormous all life would probably be sterilize within a few dozen cubic light years. The other unpleasant aspects of a supernova could be shielded against but not neutrinos, it's hopeless, you're fried.
John K Clark firstname.lastname@example.org
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