Thread: Mapping Sol
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Old August 14th, 2003, 03:58 AM

Baron Munchausen Baron Munchausen is offline
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Default Re: Mapping Sol

Heh...

Too much oxygen is poisonous because we've evolved in this atmosphere which is 70 percent+ nitrogen. A (nearly) pure oxygen atmosphere would not necessarily be impossible for life to exist in, though unlikely in 'real life' because free oxygen is chemically unstable. It's the presence of life that maintains the current percentage of oxygen in Earth's atmosphere now. It would all be soaked up in chemical compounds within a few million years without constant renewal by plants. Many simpler life forms on Earth today could handle a nearly pure oxygen atmosphere, though.

It's much the same for CO2. We humans would die in an atmosphere of more than 4 or 5 percent CO2, as I recall. This is not a universal constant but simply a function of how human physiology turned out. Lots of simpler animals can handle more than 4 or 5 percent CO2.
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