some
meteorite statistics
Nearly
all meteorites are found in deserts (yes, Antarctica is a desert
because the annual precipitation rate is very low). Deserts are
places that collect meteorites over thousands of years and nothing
much happens to the meteorite. Also, meteorites are easier to find
in deserts then they are in places with lots of vegetation or other
rocks.
Meteorites are found in Antarctica by government funded
expeditions, mainly form the U.S. and Japan. Nearly all have been
found since 1976. Many meteorites have been found in the Sahara
Desert of northern Africa, mainly by private collectors. More meteorites
have been found in Oman, a desert country about the size of New
Mexico, than in all of North America (Canada, Mexico, U.S.). Nearly
all of the meteorites from Oman have been found since 2000.

Only a small fraction of meteorites are observed to fall,
2.8% for the whole world. The proportion of meteorites that are
falls from North America is larger than that for the whole world
because most meteorites come from the deserts of Antarctica and
Africa, places where meteorites are rarely observed to fall. Also,
nearly all meteorites found in deserts fell long before humans actively
sought them.

Most meteorites that fall on Earth are stony meteorites.
Only a few percent are irons. However, in populated places like
North America, people find a greater fraction of the irons because
irons tend to be bigger* and are more likely to catch peoples' attention.
*Although only 2.6% of meteorites are irons, 85% of the
mass of all meteorites is in the irons. 11% of the mass is in the
stony meteorites.

Most stony meteorites are chondrites, and most chondrites
are ordinary chondrites.
Chondrites contain iron-nickel metal,
which is what makes them attracted to
a magnet. Most other meteorite types have little metal. The
achondrites resemble Earth rocks more closely than the other meteorite
types. The proportion of achondrites among stony meteorites may
be less than the 4.6% indicated here because among the 20% of meteorites
that have been found in Africa and Oman (above), collectors have
not reported all of the ordinary chondrites but most of the achondrites
have been reported because they sell for higher prices.
All data presented here was gleaned from the Meteoritical
Bulletin Database of The
Meteoritical Society. See also Wikipedia's "Meteorite
fall statistics." |