[meteorite-list] NASA finds extra-terrestrial amino-acids in Sudan meteor...

From: Martin Altmann <altmann_at_meteoritecentral.com>
Date: Fri, 31 Dec 2010 14:39:13 +0100
Message-ID: <000c01cba8f0$2030fd50$6092f7f0$_at_de>

I understood rather, that it was meant, that they, using a collision model
for the formation ureilite parent body,
that the temperatures occurring in such an event annihilate the amino acids.

About temperatures of the atmospheric passage, when a meteorite fells, we
don't have to care.
Just look on a cross section of a fresh stone fall or a Sikhote, and you
see, that there were no such high temperatures at work inside.
As well as we have enough preserved amino acids in various carbonaceous
chondrites, CM, CR, CV...

So I think, it's about these amino acids formed after that collision event,
whether there are other mechanisms necessary than those, how the amino acids
were supposed to have formed in carbonaceous chondrites.

And here is also a problem, that the formation and the formation history of
the URE-parent-body seems to have been very complex and not yet fully
understood.

As always in such cases, David Weir gives the best overview about the
competing concepts.
(One of them contains btw. also aqueous alteration).
http://www.meteoritestudies.com/protected_KENNA.HTM

Also I think, heating by later impact events, like commonly happening on
asteroids in building regoliths on the surface isn't meant.
Almahata is a polymict breccia, a jigsaw made of various ureilitic
lithologies as well as of ordinary and enstatite chondrites, even R-related
clasts were found, hence a mixed breccia, which we know of other meteorites
too, although with Almahata the mixture of the different constituents is
very special.
With such high temperatures mentioned, the primitive chondrite fragments
wouldn't be preserved.

Unfortunately the articles say nothing about, in which of the lithologies in
that breccia, the amino acids were found.


So if I understood the article correctly, it's about, how the formation of
amino acids could fit in the theories of the formation of the ureilite
parent body.

(The use of such vocables like "impossible" or "forbidden" in such articles
with a character of popular science, are stylistic devices to attract the
attention of the readers).

Btw. (and promised, for the last time in the year)
that Murchison is almost a synonym for extraterrestrial amino acids,
has two reasons. History, it felt just when the labs, waiting for the
Apollo-rocks were ready,
and secondly, with 100-150kgs it has by faaaar the largest tkw of all CMs,
hence a kind of 869 among the CM2.
Hence time and it's comfort availability made Murchison to that what it is.

Nowadays scientists have so much greater possibilities!

Huh, if I look only into the Chladni's Heirs portfolio of the very recent
few years.
Three different new CM2s, all with a preservation equivalent of W0 to W1,
the first CM1 outside Antarctica,
16 different CKs, a CR2 less weathered than the average, various COs and
CVs, a "C" without nothing, not to mention the ureilites...

...and we are only two out of many private dealers and hunters!

So, (to tickle Jason, hihi, although the amino acids possibly to be found in
these do have no terrestrial coordinates),
I think, that that kind of herostrati, arguing for a complete ban of
finding, trading and private collecting,
hence those, with the extremely "conservative" concept, that meteoritics
should be mainly the administering and preserving of old specimens as
national and historic curios and that the meteorite in the drawer or
decaying unfound in the soil garnished with a wreath braided of cheap morals
and expensive envy, is a higher good than the meteorite in the microprobe,
should now learn, not only that really not all of their colleagues are eager
to work only and always on Murchison,

but also that without the private finders, dealers aaaaaaand mainly the
private collectors, it doesn't work.

The private collectors, who nowadays almost alone are funding the recovering
of all these fantastic new possibilities, the stones, which still have so
much to tell about our solar system, the life and in the end about: us.
With each specimen they purchase.

For that the meteoricists owe great gratitude and respect to them,

as well as we want to express now our thank to the collectors for this year,


looking forward to the upcoming year,
which, although the dark powers of brutish- and ruthlessness in some
countries
were raging the past year like never before,
shall be a turning point for the return to the find numbers we all once had
and the advent of an era of reason, joy and true enthusiasm.

Because these stones, which so persistently resist being found,
they have still so much to tell to us.


In this spirit: Happy Finds & Findings to All in 2011!

Martin
Received on Fri 31 Dec 2010 08:39:13 AM PST