Hey 2cents,

Completely agree with your point about having a mentor. A lot of good "out of the box" thinking occurs however, when fresh eyes approach a problem.

I just wanted to touch on your question of "If the mantles were going to open...why not at their present orbit position?"

Currently, out-gassing is occuring from mantles on all the terestrial planets in our solar system. Even Mercury has a small amount of atmosphere. Think of it as simply the gases that flow into the atmosphere following a volcanic eruption. The gases are derived from molton rock and elements.

Scientists now propose that earths early atmosphere was a toxic mix of methane and ammonia, which is similar to what we're seeing on Venus at the present.

I'll look around for one of the papers I had on atmospheric development, but here's a link to another site on proposed atmospheric history in the meantime.

C-ya later, Billion

• Earths Atmosphere history