[meteorite-list] Recognizing a Venusian meteorite

From: Sterling K. Webb <kelly_at_meteoritecentral.com>
Date: Thu Apr 22 10:28:35 2004
Message-ID: <3F99D400.EB0D2D1F_at_bhil.com>

Hi,

    Actually, there are a number of sedimentary meteorites. It's just that
they are not acknowledged to be meteorites.
    If you have the CDROM of the Catalogue, have the software assemble you a
list of "pseudometeorites" that are not irons.
    Or just search for BLECKENSTAD (April 11, 1925) SWEDEN, a sedimentary
meteorite of white limestone complete with fossil shells. It was reported on
by Dr. Assar Hadding of the Swedish Geological Institute in 1939 who after a
long investigation decided it really was a meteorite. The chief reason for
so believing is that it is a WITNESSED FALL and you really can't get much
better than that. However, he was widely regarded as whacky by the wise men
of 1939 and (equally wisely) shut up about it for 20 years. Hadding was so
discouraged by the reception of his earlier paper that, when he discovered
another sedimentary meteorite, he threw it away! Only much later, when he
realized that they could have been "Earthites," did he write about the two
stones again.
    Nininger himself found a small sedimentary meteorite, on March 24, 1933,
while searching for fragments of Pasamonte. The stone in question was a
dirty grey limestone with fragmentary shell bits fossilized in it and
sporting a black fusion crust. He ruled out an artificial origin for the
crust but was unwilling to claim it was a meteorite, apparently not because
he didn't think it was a meteorite but because it wasn't worth the noise...
    Frank Cross wrote about sedimentary meteorites at length in the journal
"Popular Astronomy" (Vol. 55, 1947, pp. 96-102), citing Trevlac (Indiana)
and Montrose (West Virginia), two independently discovered sedimentary
meteorites with identical green glassy crusts.
    And so it goes...
    The whereabouts of most of the sedimentary "pseudometeorites" is
unknown, not surprising considering their reception, so the sophisticated
tests that could be performed today are impossible. There's a kind of
self-reinforcing judgement at work in that. Two guys from the French
Academy, flumping their powdered wigs, explain, "Foolish peasant! Ze
sedimentary rocks from ze sky, zey do not fall," so we throw the evidence in
the trash.
    Anybody on the List know what happened to Nininger's sedimentary find?


Sterling K. Webb
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mark ford wrote:

> More to the point where are all the earth meteorites? We should be able
> to recognize them, (one would hope!), I guess as most of the earths
> immediate surface is soil, or sedimentary rock(s), an earthite meteorite
> would be pretty strange do date no true 'sedimentary' meteorites have
> been found?, I guess it would probably look like a tektite I.e silica
> glass... or would they be just be highly shocked ordinary terrestrial
> rocks but with a fusion crust?
>
> Mark Ford
>
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Received on Fri 24 Oct 2003 09:38:09 PM PDT