[meteorite-list] (no subject)

From: rochette <rochette_at_meteoritecentral.com>
Date: Thu Apr 22 10:25:42 2004
Message-ID: <a05100300baf0389733e1_at_[193.250.222.239]>

>Hello all,
>
>I really needed to take a break, so I was perusing the "Catalog of
>Antarctic Meteorites" from the National Institute of Polar Research,
>Tokyo, 1995.
>And in there I find Yamato-790146, classified as Terrestrial. Why
>classify an antarctic specimen as terrestrial - why not just chuck
>it? Or is it a terrestrial meteorite?

well this sample was collected, numbered, bagged, transfered from
Antartica to Japan and catalogued and stored carefully among
thousands of other Yamato samples. It is only after a while (may be
years!) that a thin section was made and that terrestrial origin was
revealed. It was too late to cancel the entry in the catalogue. it is
also good scientific procedure to keep record of failures instead of
just throwing them, for the edification of the next generation of
scientists. These samples can also be of scientific interest for
example to calibrate isotopic techniques. It sounds silly not to have
recognized it right from the beginning but in Antarctica the
conditions are not such that you can observe carefully all samples
and also great care is taken to avoid contamination so that the
samples are bagged and sealed right after discovery.

There are terrestrial sample catalogued in other Antarctic meteorite
collections. There are also non antarctic meteorwrongs in the
Cambridge Catalogue of Meteorites.

By the way the large number of unique types in Yamato collection may
be due to the fact that they dare collecting samples that did not
look like usual meteorites!

-- 
Pierre

Received on Tue 20 May 2003 03:56:47 PM PDT