>CurtAdams@aol.com wrote:
>> I would think that if such events are truly as common as this, the
prognosis
>> for long-term space colonization is poor. It would be very hard for a
>> space-based civilization to sustain hundreds of years of hard radiation at
>> such intensity that an atmosphere is insufficient shield. Even planetary
>> based nanotech using civilizations would be very strained by such events.
>That technicium levels in molybdenum deposits indicate the existence of
>such gamma ray bursters in our own geological past (supposedly the late
>cretaceous), or that our sun was once eight times as bright as it is now
That's fascinating. Do you have a reference I could look at? Were there any
other such events?
>Once we've
>expanded past the limit of possible extinction, then any such
>catastrophe thereafter is simply a stumble in our march across the
>skies.
Depends on how fast we can expand, which isn't yet clear.
>Besides this, I expect that technology will allow
>the development of sheilding sufficient to protect any "Noah's Ark" type
>preserves, possibly in the cores of asteroids or dead moons like our
>own. Several hundred miles of solid rock in every direction should be
>enough sheilding against anything two neutron stars can cook up from
>several hundred light years away.
Noah's Ark is a myth, remember. You can survive in a "Noah's Ark", but a
civilization can't (nor an ecology). Complex civilizations need very large
numbers of people to support them. And imagine the chaos created if a solar
system-wide civilization discovered 99.9% of the population was going to die
in the near future? I'd expect the fighting to destroy the Arks.