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Re: Meteorite weight?
RE "average" weight of a meteorite:
The best figures I have seen were, I believe, in THUDERSTONES &
SHOOTING STARS, by Dodd. There is a dramatic graph depicting size and
frequency of fall. I believe that "micrometiorites" fall at a rate of
aprox. 10,000 per day, with dramatic decreases in frequency - up to
massive sized meteorites every 1 Million years - though, don't quote me
on this - it is the idea I am conveying, not the specifics of the
details - the point is, size & frequence have a pronounced inverse
relationship & Dodd charted it - probably, within relatively acurate
limits.
OK, here we have it - page 4 - Dobbs breaks them up into 4 sizes:
Cosmic dust particles - so small they are not subjected to ablation
upon passage through our atmossphere (these fall as dust -
millions daily)
Micrometeorites - which includes all ablated material & "dust"
from an exploded bolide.
Recovered meteorites - the typical specimens in collections, ranging
in size from about 1/2 gram to several hudreds of grams &
occasionally, several dozens of kilos. He calculates meteorites
up to 1 gram hit the earth about1.6TRILLION times a year.
1Kg sized - 1 million a year.
Crater forming meteorites - by this time, he has it down to about
every 100,000 years, IF you are talking about craters the size
of Arizona Meteor Crater. (he gives an extimate of 350 tons as a
minimum size for a meteorite to make it through our
atmosphere while maintaining original speed -anything smaller
is subjected to having its "fall broken" by the intense pressure
build up amassed at its front - The meteorite strike in Az was
MUCH larger than 350tons. He figures 5 meteorites a year
strike earth with sufficient force to cause a crater of some size.
One thing to remember is that the earth is covered with water over 71%
of its area - the other 29% - the vast majority of meteorites go unseen
during their fall to earth & unrecognized & never recovered - they
become part of the earth's surface by degridation.
I would like to address some of the "smart ass" responses given to this
question. There are no dumb questions - there are, however, some dumb
answers. When people take an elitist position it really is unacceptable
& deffinately NOT in the best interest of anyone. All it does is
discourage the asking of questions.
References: