[meteorite-list] Extra-solar material?

[Chris Peterson]

I recall an analysis that predicted the rate we might encounter 
extrasolar material, and it was high enough to suggest that the Earth 
has actually crossed paths with such stuff. But statistically, the 
velocity of extrasolar material is likely to be very high- well above 
the solar escape velocity- and we know both empirically and 
theoretically that this doesn't bode well for meteorite production.

Extrasolar meteors have probably occurred; extrasolar meteorites seem 
unlikely.

Chris

*****************************************
Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com


----- Original Message ----- 
From: "Norbert Classen" <riffraff at timewarp.de>
To: "'Mark Crawford'" <mark at meteorites.cc>; 
<meteorite-list at meteoritecentral.com>
Sent: Saturday, May 03, 2008 9:01 AM
Subject: Re: [meteorite-list] Extra-solar material?


Hi Mark,

The nano diamonds in Allende CAI's are considered to be samples of
extra-solar origin; at least they show isotopic values that don't match 
with
any of the other values measured for materials of our solar system
(including meteorites).

I believe there were studies of other (Antarctic) carbonaceous 
chondrites
which also were shown to be from other systems, but right now I don't
remember the exact publication. Should have been in MAPS, but I would 
have
to look this up, first. Bernd: do you have an idea where I might have 
read
about it?

But as far as I know no meteorite as such has been considered as
"extra-solar", so far - these are always inclusions, and most of them 
are
microscopically small.

All the best,
Norbert