Re: Life Atmosphere Basically the same everywhere? (resend)

On Dec 4, 1:24=A0pm, Tom Hendricks <tom-hendri...@xxxxxxx> wrote:
There seems to be a major restriction on all life that many don't conside=
r. Only a planet about the size of Earth will hold in an atmosphere that wo=
uld lead to the origin of life. A planet with a larger atmosphere like Jupi=
ter retains too much of the wrong gasses.
Are you sure about that? Maybe Jupiter has the exact right
atmosphere.
Also, I think you are wrong about the gravity of a planet having a
great affect on the composition of its atmosphere. All atmospheres are
unstable in an inverse square gravitational field. Eventually, all
atmospheres evaporate. The atmospheres with high molecular weight will
last longer than the ones with low molecular weight, to be sure.
The composition would have more to do with age and temperature
than gravity. and maybe photochemistry. Then there is volcanic
activity... The gravity is only one factor.

.

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