[meteorite-list] Chondrule formation mechanism

[Darren Garrison]

On Sat, 21 Oct 2006 16:41:48 -0700 (PDT), you wrote:

>> Chondrule textures depend on the extent of melting
>> of the chondrule precursor- material when cooling 
>> starts. 
>
>Kind of begs the question - chodrules formed by
>collision, which causes melt - consider if one started
>from a steady molten state 
>
>>If "viable nuclei" 
>
>I wonder what these "viable nuclei" are? viable cystal
>nuclei=Chondrules?

How things appear to be (without trying to refer to chemical/minerological
details that are beyond my level of knowledge) is that what became chondrules
started out as "fluff" that slowly accumulated from the solar nebula, like you
mentioned earlier.  I imagine something like snowflakes, or dust-bunnies.
Something fragile and irregular filled with empty spaces.  Then, something (and
there is no consensus on what that "something" was) heated those
dust-bunnies/snowflakes up to the point where they melted-- and in a
microgravity environment surface tension pulled them into little spheres.  The
"viable nuclei" means parts of that original fluff that didn't fully melt and
became seeds for the new minerals to grow on.