From: David Madison (maddad_at_Maddad.org)
Date: Tue Jan 07 2003 - 18:40:39 PST
The problem with that analysis is that the term "Very Old" is relative. How
old do we have to be to be very old? What you need for high metallicty in a
solar system is several previous generations of stars in the gas cloud that
condenses into that solar system. In an area of intense star formation you
have lots of massive stars living out their lives at 100 million years
apiece. Four generaions later, less than a half billion years into the
game, you have high metallicty for the raw material of an intelligent
space-faring race.
Spectrographic analysis of starlight should show us the concentration of
heavier elements in the atmospheres of those stars. We might just be able
to observe an answer directly.
_________________________
Chances for earth-like planets and life around metal-poor stars
http://www.spaceref.com/news/viewsr.html?pid=7478
We discuss the difficulties of forming earth-like planets in metal-poor
environments, such as those prevailing in the Galactic halo (Pop II), the
Magellanic Clouds, and the early universe. We suggest that, with less heavy
elements available, terrestrial planets will be smaller size and lower mass
than in our solar system (solar metallicity). Such planets may not be able
to sustain life as we know it. Therefore, the chances of very old lifeforms
in the universe are slim, and a threshold metallicty (1/2 solar?) may exist
for life to originate on large enough earth-like planets.
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