Is Earth's Atmosphere an Import?

garg0yle writes "One of the questions about the formation of our planet is: where did the atmosphere come from? One theory is that the oxygen, nitrogen, and other gases were part of the coalescing ball, and 'seeped out' during the final stages of the planet's formation. However, a new article at Wired says isotopic analysis of krypton and xenon indicates that they (and the rest of our atmosphere) may be of extraterrestrial origin, either arriving via comets or being swept up from gas clouds."

Re:Wha...?

[wizardforce]

Incorrect. Isotopic ratios vary depending on the conditions in the planetary nebula that formed our solar system. The disk tends to fractionate into "layers" with refractory materials tending to be toward the sun and volatiles tending to be fairly far away from the sun. Volatiles like Hydrogen and Helium would be expected to accumulate around large terrestrial masses ~50 Earth masses out around Jupiter and beyond. Volatiles like Hydrogen and Helium don't accumulate as significantly near terrestrial planets as close as the Earth is due to the fact that the Earth and similar terrestrials were of insufficient mass to retain significant Hydrogen and Helium. This is due in large part to the density of the nebula which formed our solar system.

Re:Science?

[repepo]

How the HELL did this article get filed under "science".

Venus has a significant atmosphere. Saturn has an atmosphere. Neptune... atmosphere. Jupiter... ALL atmosphere. Hey, look at that! All the planets larger than Mars have a significantly thick atmosphere.

Maybe it's as simple as their gravity is sufficient to trap gasses.

Please refile this article under "Intellectually Bankrupt" instead.

I think the question is the origin of the gases, not the mechanism that keeps them trapped.

Re:Who cares?

[TimSSG]

FYI:

The is only a single Solar System in this universe.
That is the name out our star system. Please use star system instead of Solar System when not referring to our star system.

Tim S.