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Re: Meteorite Trivia Questions

At 06:50 PM 3/2/98 -0800, you wrote:
>Does anyone know why OLD HOMESTEAD 001 (the howardite from Nullabor,
Australia) has the 001 designation in its name???
>
>Similarly, why does REID 013 (the brachinite from Nullabor, Australia)
have the 013 in its name???  (There is an older Reid H4 chondrite not to be
confused with Reid 013)
>
>The numbering of Saharan meteorites makes some sense because there are no
nearby landmarks in the vast desert, but the numbers in these two
meteorites is a complete mystery to me. 
>
>Someone asked me, and I said, "Heck, if I know."
>
>Steve
>Seattle, Washington USA
>excell@cris.com
>
>

Welcome to the exotic world of meteorite nomenclature.  These meteorites
are, as you say, from the Nullarbor Plain spanning Western Australia 
and South Australia.  Like the Sahara, the Nullarbor has very few
named geographic features for which meteorites can be named.  Yet, 
there are currently 244 described meteorites from the Nullarbor, in
need of names.  

Alex Bevan, from the Western Australia Museum, proposed
a system for naming these meteorites (Bevan and Binns, 1989, Meteoritics
24, 127-133 [for Western Australia], and Bevan and Pring, 1993,
Meteoritics 28, 600-603 [for South Australia]) in which the region
is divided into 71 mostly-rectangular areas averaging ~3000-4000 km^2,
each with a designated name.  This system was adopted by the Meteorite
Nomenclature Committee; now, all newly found meteorites are plotted
on this grid, and given the next available number for the region in
which they were found.

Thus, there are currently 2 Old Homestead meteorites (Old Homestead
and Old Homestead 002), and 15 Reid meteorites (Reid, and Reid 002-015).
Note that there are some "grandfathered" names in this region that do
not bear the names of their designated grid cells, and in some cases,
like Reid and Old Homestead, there is no "001" case (although nobody
gets confused when Old Homestead is called Old Homestead 001).

Attached is a map, for your amusement, showing the Nullarbor
meteorites. The color codes for meteorites are:
	Ordinary chondrites:  Dark blue
	Carbonaceous chons:   Lt. blue
	Enstatite chondrites: Orange
	Iron meteorites:      Red
	Achondrites:          Green
	Pallasites:           Purple

-jeff

nullarbor.JPG