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RE: starship-design: WHERE ARE THEY?
L. Parker writes:
> > If this is true then gamma-ray burst events are even more common,
> > but we can see only those whose beams point at us. However, it
> > is then unlikely that gamma-ray bursts can sterilize galaxies.
> No, it doesn't change the end result at all as far as the equation is
> concerned. It just means that there are more of them to make up the
> difference. Statistically, the end result is the same. We seem to have just
> been extremely lucky in that none have been pointed our way in somewhat more
> than the allotted amount of time.
Actually, plenty are pointed our way -- otherwise we wouldn't
keep detecting them so frequently.
Statistically, though, the result is not the same. On a
universe-wide scale, there are plenty of gamma-ray bursts for
everyone to see. If GRBs are isotropic, then, yes, potentially
each burst we see has sterilized a large portion of its host
galaxy. But if GRBs aren't isotropic, then individual GRBs
aren't sterilizing huge parts of the galaxies they occur in, and
at a galaxy-wide scale there aren't enough close GRBs to clear
galaxies of life.