[meteorite-list] Meteorite reclassification questions

From: Michael Doran <eikoph_at_meteoritecentral.com>
Date: Thu, 14 Mar 2019 15:38:29 +0000 (UTC)
Message-ID: <1617947328.5501379.1552577909317_at_mail.yahoo.com>

Thank you to all who answered.? Your replies were very helpful.??

-- Michael

Michael Doran
Fort Worth, TX

On Wednesday, March 13, 2019, 11:06:19 PM CDT, Michael Doran <eikoph at yahoo.com> wrote:

As a newbie, I've come to rely pretty heavily on the Meteoritical Bulletin database for information about particular meteorites as well as to look at aggregate data for different types.

I've been somewhat surprised to discover that it is not unusual for meteorites to get reclassified and I was wondering if anybody could tell me how and under what circumstances a Met Bull entry gets updated to reflect new classification information.

Ningqiang is a good example of reclassification updates.? The Meteoritical Bulletin database entry shows that Ningqiang was originally classified as a CV3, per Meteoritical Bulletin #65 (1987) [1]. Then (if I'm interpreting the entry correctly) it looks like it was reclassed as a CK3, per the Natural History Museum's Catalogue of Meteorites, 5th edition (2000).? And a subsequent reclassification as C3-ung came per the 7th edition of MetBase (2006).

The particular example I had questions about is the entry for Hart, a Texas meteorite found in 2010 and that was initially classified as a CK3 [2].? CK3 is a pretty rare carbonaceous chondrite type and Hart was apparently the only meteorite in the U.S. to get that classification.? However, I recently came across a scientific paper ("Reclassification of Hart and Northwest Africa 6047: Criteria for distinguishing between CV and CK3 chondrites" [3]) that appears to make a persuasive case for Hart being reclassified as a CV3. This paper was published in 2017, but there is no update yet in the Met Bull entry.

So my questions are:

1) Will the Meteoritical Bulletin database entry for Hart eventually get updated to reflect a change in classification?

2) What mechanisms (if any) are in place to keep track of these types of reclassifications and make updates? (From what I've seen, there is a mechanism for Antarctic meteorites via the Antarctic Meteorite Newsletter. See, for example AMN item on reclassifications [4] and subsequent Met Bull database entry update [5].)

3) Is there some body that mediates between competing classification claims?? E.g. what if the original classifier disagrees with a reclassification?

-- Michael

[1] https://www.lpi.usra.edu/meteor/metbull.php?code=16981

[2] https://www.lpi.usra.edu/meteor/metbull.php?code=56555

[3] Dunn, TL, Gross, J. 2017 Reclassification of Hart and Northwest Africa 6047: Criteria for distinguishing between CV and CK3 chondrites. Meteoritics & Planetary Science 52(11):2412?2423

[4] https://curator.jsc.nasa.gov/antmet/amn/amnfeb10/reclassifications.htm

[5] E.g. for EET 96010 https://www.lpi.usra.edu/meteor/metbull.php?code=9604

Michael Doran
Fort Worth, TX
Received on Thu 14 Mar 2019 11:38:29 AM PDT