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Since Life needs very specific conditions in order to exist and develop (radiation level, sunlight, temperature, presence of air and water, etc...) can we assume that if life exists elsewhere in the universe, it will ressemble pretty much what we have here on Earth (ADN structure, metabolism, carbon based)?
This is pure guesswork on my part. The conditions for the sort of life we find on different parts of the earth match the conditions on those parts. Life is found over quite a wide range of temperatures. pressures, pH's, etc. My guess is that the possible range is larger than the range of conditions on Earth, and that the range of life chemistry would also be larger than found here. That is not to say that life could exist under any conditions whatsoever. For example, it's very hard to see any thing stable and complex enough to be called life existing on a hot star.
(published on 07/12/2010)
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