[meteorite-list] Extra-solar material?

From: Sterling K. Webb <sterling_k_webb_at_meteoritecentral.com>
Date: Sat, 3 May 2008 14:14:42 -0500
Message-ID: <09f201c8ad51$f18105a0$db45e146_at_ATARIENGINE>

Hi All,

    The AMOR radars that are used to detect
meteoroids at altitude all find a few percent of
them have velocities too high to have originated
in our solar system's gravitational family. The
fast particles have a preferred origin, from which
more than a quarter of them originate, a patch of
sky centered around the nearby young star Beta
Pictoris, known to have a large dusty disk that
may be proto-planetary.

    Of course, for any number of small particles,
there is a smaller number of the next largest size,
and so on, ad infinitum, the numbers related by
a power law. So, there are some chucks big
enough to interest those who want meteorites
bigger than dust! But they're rarer.

    However, this implies that most of those chunks
would more likely be YOUNGER than our solar
system, as it is the younger (and dustier) forming
star systems that produce them. A universe full of
OLD chunks would be a universe that made billions
of stars and solar systems, but stopping doing it
once it had produced the perfect place (with the
perfect beings) that is the center of the universe,
namely US! While that is the usual human view,
it does not seem that's the way the universe works.

    While there certainly are still old chunks drifting
around the universe, our Sun is located in a star
forming region of our galaxy, surrounded by many
stars younger than it is because we're in a nursery!
The process of star formation, planetary formation,
and early bombardment produce far more chunks
than the older settled life of a star, so at any time,
the majority of the dust and chunks reaching us are
from younger systems.

    In regions where stars are more crowded together,
like star clusters, particularly young ones, solar systems
probably exchange chunks between each other with
great frequency. At least, the study reported here says so:
http://www.universetoday.com/2005/05/04/did-life-arrive-before-the-solar-system-even-formed/

    Additionally, such clusters would continue to produce
impact products throughout their lifetime at a rate much
greater than, say, a solar system like ours, even an older
cluster (some are almost as old as the universe) could
be distributing material widely, some of it big enough to
transport life (if that's what you're interested in). If there's
no life in your neighborhood, just wait a few billion years;
it will show up.


Sterling
---------------------------------------------------------------------
If you're interested in the AMOR radars and the radiants
of extra-solar material, just Google "AMOR radar." You'll
get a lot of references, none of them available without
subscription or fee... as usual. All part of the successful
cultural program to promote ignorance.
---------------------------------------------------------------------
----- Original Message -----
From: "Chris Peterson" <clp at alumni.caltech.edu>
To: <meteorite-list at meteoritecentral.com>
Sent: Saturday, May 03, 2008 11:04 AM
Subject: Re: [meteorite-list] Extra-solar material?


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

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Received on Sat 03 May 2008 03:14:42 PM PDT