[meteorite-list] Questions about accretion.

From: Meteorites USA <eric_at_meteoritecentral.com>
Date: Sun, 05 Apr 2009 12:52:46 -0700
Message-ID: <49D90C0E.4030108_at_meteoritesusa.com>

Thanks for the responses thus far...

I've studied lots of material and scientific papers on accretion, but
still have some questions. The gravity explanation is great, but it's a
little vague. I want to know what causes it I guess at the molecular
level. What physical forces and interactions cause the iron to migrate
into such a solid mass at the core?

If gravity alone were the case, why is it we have H and L chondrites at
all? Everything would be one big clump of mixed material. Has the iron
not had a chance yet to migrate out of this layer of rock to the center
of the asteroid? I know H and L chondrites are meteoroids that have
broken off the parent bodies but my question is simply, had they not
been blasted off the main body, how long would it take and in what
manner would the iron have migrated from these layers of rock to the
core? Iron doesn't just move through stone without some sort of catalyst
or outside force does it? Gravity itself is not sufficient to move iron
through a stone matrix no matter how much time passes is it? If there
are no impacts or outside forces acting upon the body how does the iron
loose itself from the grasp of the stone matrix to move through toward
the core? Impacts?

At the beginning of the formation of a meteoroid is it electrostatic
attraction that causes it to get larger? At what size does it produce
it's own gravity? Or does it? How does and asteroid become so dense? If
asteroids are super dense, and comets are loosely bound material and
gases, would that mean that asteroids are dead comets?

Wow! I know that a lot of questions. sorry... ;)

Eric
Received on Sun 05 Apr 2009 03:52:46 PM PDT