LRP,
You need to use two equations; one to find the orbital velocity of your planetisimal as it grazes the atmosphere, and the other to find its kinetic energy as it actually enters the atmosphere. If you understand that the falling body converts kinetic energy into heat energy via friction, then you will finally how your theory results in the vaporization* of the oceans, melting of the entire crust and much of the mantle.
There is no need to return until you can show your work solving those two equations.
{edited to add *vaporization... doh}
[This message has been edited by wehappyfew, 01-31-2003]
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