[meteorite-list] Fusion Crusted "Meteoroids"

From: Darren Garrison <cynapse_at_meteoritecentral.com>
Date: Wed, 25 Mar 2009 11:57:38 -0500
Message-ID: <pnnks494v3ufeovaknu37ggq4acuqfunc9_at_4ax.com>

On Wed, 25 Mar 2009 08:21:58 -0700, you wrote:

>How many beautifully black and fully fusion crusted meteoroids and
>asteroids are floating around out there in space?

A fusion crust is formed by the rapid melting and rapid resolidifying of the
meteoroid, caused by heat generated by a meteoroid passing through the
atmosphere of a planet, decelerating, and having some of it's massive amount of
kinetic energy converted to light, sound, and heat, due to conservation of
energy. So a meteroid in space with a fusion crust would have had to have
grazed deep enough in to the atmosphere of a planet or moon and then skipped
back into space. Any attempt (by anyone, no matter how expert) to give an
approx. number of times that this has happened on all atmosphere-posessing
planets and moons AND the meteoroid wasn't destroyed on a later pass near the
planet/moon AND it hasn't happened so long ago that the normal erosion in space
has broken up that fusion crust would be a pure guess. This MIGHT be one:

http://en.wikipedia.org/wiki/The_Great_Daylight_1972_Fireball

I can imagine that a massive nearby gamma ray burst might also be able to melt a
thin fusion crust around meteroids in space, but if such an event had happened
in the recent geological past, we would have noticed it by the fact of all being
dead.
Received on Wed 25 Mar 2009 12:57:38 PM PDT