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Re: Astro Physical Geology

paul o johnson wrote:

The piece goes on to speculate that there may be many early Earth rocks,
... lying about on the moon's surface.

OK...

some carrying early bacterial life

I don't know about that. Bacteria postdate the presence
of an atmosphere. Think about the fiery flight of a
meteor. Going UP through the atmosphere at orbital
velocities must be at least as violent, so I'd expect
most of the bacteria to be pretty well toasted. And
the impact with the moon, once the moon was well-formed
enough to have a "surface", would be pretty toasty, too.


... every impact not only added to but likely subtracted from Earth's
mass.

Not _every_ impact, not by a long shot. Only reeeeally
violent impacts can subtract.

Has any planetary scientist addressed this question?

Presumably all of them. This is pretty much the standard
moon-formation theory nowadays.

This posting is the position of the writer, not that of Artemis, Hecate,
Bendis, Brizo, or Diana.

This posting is the position of the writer, not that of SUNY-BSC, NAU or the AAPT.