meteorites question: Dar al Gani 488

Hi all,

Little question to the meteorites specialists he

I just have got a bit of DaG 488, and as I'm complete newbie I wanted to
know some more about it. By searching the internet I've seen that there are
a lot of different DaG numbers. Some pieces are said to be lunar such as DaG
262, some from Mars as DaG 489...
Is it possible that in this "small" part of Lybia is a concentration of
meteorites from Mars, the Moon and wherever else ?...

I'd be pleased if somebody would tell me a little more about DaG 488, or on
Dar al Gani in general, or provide me good pointers to useful information.

Thanks very much in advance, Eric

PS: Edd, I'm sure you'll see my post :-)

In article ,
Eric Voisard wrote:
a lot of different DaG numbers. Some pieces are said to be lunar such as DaG
262, some from Mars as DaG 489...
Is it possible that in this "small" part of Lybia is a concentration of
meteorites from Mars, the Moon and wherever else ?...

Almost certainly there's no concentration -- it's just a good place to
*look* for them. There are a *lot* of meteorites on Earth; for example,
it's been estimated, if I recall right, that a couple of tons of Mars
rocks fall on Earth every year. The trick is finding them.

What you want is a large area of bare surface where there's no vegetation
to hide small rocks, and where -- for one reason or another -- there
aren't very many Earth rocks confusing the picture. Preferably a place
that's been stable for a long time, so there'll be many years'
accumulation of meteorites. When such a place is identified, it tends to
get intensive attention from meteorite hunters, so an awful lot of the
known meteorites come from a few small areas of the world.

This doesn't mean that there aren't just as many elsewhere. But in most
parts of the world, you can't find them unless you get lucky.
--
"Think outside the box -- the box isn't our friend." | Henry Spencer
-- George Herbert |

Hi Henry,

Almost certainly there's no concentration -- it's just a good place to
*look* for them. There are a *lot* of meteorites on Earth; for example,
it's been estimated, if I recall right, that a couple of tons of Mars
rocks fall on Earth every year. The trick is finding them.

Thanks for the answer. I makes a lot of sense!
From this point of view I understand much better the story, and how
different it is than hunting fragments in places where a single well known
meteorite has fallen (such as in Sikhote-Alin, Siberia).

So, as there are quite few of information from DaG 488, could I guess that
at least it hasn't been recognized as a piece of Mars or the Moon, and that
it most probably comes from some asteroid...

Thanks again, Eric

In article ,
Eric Voisard wrote:
So, as there are quite few of information from DaG 488, could I guess that
at least it hasn't been recognized as a piece of Mars or the Moon, and that
it most probably comes from some asteroid...

People are now alert to the possibility of Moon and Mars meteorites -- in
particular, private meteorite hunters are very much aware that verified
Moon and Mars meteorites are *much* more valuable -- so a meteorite not
identified as such almost certainly isn't one.

So yes, you've probably got a piece of asteroid there. The details are a
bit fuzzy in places -- notably, there is a long-standing discrepancy
between the distribution of meteorite types (about 70% ordinary
chondrites) and the distribution of asteroid spectral types (only a very
small minority reflect light like ordinary chondrites) -- but that's
clearly where most meteorites come from.
--
"Think outside the box -- the box isn't our friend." | Henry Spencer
-- George Herbert |