Re: The Extinction Challenge

Michael S. Lorrey (mike@lorrey.com)
Fri, 30 Jul 1999 03:25:19 -0400

phoenix@ugcs.caltech.edu wrote:
>
> "John Clark" <jonkc@worldnet.att.net> 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.
>
> > 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.
>
> Actually, this has been discussed on rec.arts.sf.science, and it was said
> supernovae neutrinos would be lethal in only a few AU. See
>
http://www.tass-survey.org/richmond/answers/snrisks.txt
> with calculations.
> But conversely,
> http://www.sciam.com/0496issue/0496scicit02.html
> claiming stars can collapse without being supernovae, and generate enough
> neutrinos to at least cause lots of cancer.

Which only affects those on one side of the planet. Anyone on the dark nappytime side just has to deal with a worldwide tsunami, assuming the entire atmosphere hasn't already been stripped off by the swelling effects of the late red giant stage prior to the supernova.

If you are dealing with an interstellar civilization, its all a matter of what size civilization we are talking about. Its amazing what a couple thousand light years and the dust and gas in between can do to reduce your risk of GRB related skin cancers.

Mike Lorrey