[meteorite-list] Odds of finding a meteorite on Mars

[Matson, Robert]

Hi Jim/List,

> When you consider infintesimal the odds of finding a meteorite
> here on Earth after traversing as short a distance as the rovers
> have, you have to ask whether there are local factors on Mars
> which dramatically increase the number of meteorites per square
> kilometer on the surface there.

The odds of finding a meteorite on Earth after travelling a couple
miles aren't infinitesimal -- they're actually pretty good if you're
looking in the right kinds of places.  (It takes me on average about
5 hours of walking to find a meteorite.  At an average of 2.5 miles
per hour, that's a meteorite per linear 20 km.)  While the "right
kinds of places" on earth are few and far between, pretty much the
entire surface of Mars is the right kind of place:  old surfaces,
dry conditions, no vegetation ;-).

Some areas of Mars (as on earth) are even better:  minimal native
rocks.  Opportunity is in such a region.  I'm still surprised by
the SIZE of the find, and that it's an iron rather than a chondrite.
No telling how many chondrites the rovers have driven by...

--Rob