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Old September 29th, 2005, 05:50 AM
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Default Re: Semi-OT: A question on Power Ratios in Sci-fi

Quote:
Hunpecked said:
According to the article below the first stars in our galaxy formed about 13.6 billion years ago. That makes our sun, at 5 billion years, a relative youngster.

http://www.space.com/scienceastronom...ge_040817.html

But according to that same article, our galaxy is almost as old as the universe. When the universe was born, it was all hydrogen- there were no heavy elements. It is the ongoing process of star-burning that turns dull old hydrogen into stuff like carbon and oxygen that we need for life. The older the universe gets, the more hydrogen is turned into heavy elements. Therefore, looking at it the other way, as you look back in time towards the Big Bang the amount of heavy elements in the universe dwindles down to nothing.
Since these heavy elements are needed for life, shouldn't the probablilty of life dwindle away with it?

Or, to put it another way, we may be among the first life to emerge, because it's not the amount of stars that have existed over the last 13.whatever billion years that matters, it's the availability of heavy elements- and they've never been more available than right now. Give it another 10 billion years and there could be life springing up all over the place, because the universe will be a much heavier place than it is now. It may even get *too* heavy for life at some point, which would mean the Drake equation would have to factor in some sort of bell curve with "suitability for life of heavy element/ hydrogen ratio" on one axis and "time since big bang" on the other.
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