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Re: What is a Meteorite?

Dear Frankfes@UWYO.EDU wrote:
> 
>         I have asked this question many times, but there seems to me no
> absolute answer. We know that they must originate from somewhere in the
> solar system, other than planet Earth. Also we know they have different
> characteristics than Earth rocks, so that helps us to understand what a
> meteorite is. But I feel that this is too narrow a focus.
>         When we look at meteorites, we see reoccuring patterns, ones that
> we can relate to in meteorites we have actually seen to fall. Does this
> mean that anything falling to our planet will follow these same patterns?
> Could our Solar System be a breeding ground for only a few different
> materials?
>         There are 12 types of iron meteorites, 3 types of stony iron
> meteorites, approximatly 6 types of chondrites, and approximatly 12 types
> of achondrites. This totals to about 33 known types of meteorites. That
> is an awfully small amount when we consider the size of the Solar System.
>         I estimate that the Earth has over 1,000 distinctly different
> rock types. These different rock types, are subtle, but distinct enough
> to allow a division, and classification. This leads me to believe there
> are vastly more meteorites out there, to which we have no
> information.
>         Many meteorites land on the Earth. Most all are never found, and
> a very few are actually witnessed hitting the planet. Weather then begins
> to destroy the meteorite almost instantaneously. After a couple thousand
> yrs, the meteorite can be just an amorphous lump in the soil, never to be
> realized as a true meteorite. It's chemical, physical, and mineralogical
> state has been severly altered, till almost unrecognizable.
>          Perhaps many new meteorite types have been overlooked on the
> account of the above processes. Can we ignore the ones we don't know
> about? Yes we can, on the fact that we know more types may come to light.
>         However, some would argue that what meteorites we have are the
> sum total of what our Solar System has to offer, although they would
> allow some leeway in the discovery of new types, albeit very few. I make
> no effort to argue with their position.
>         I say this, that what meteorites we have sampled are more than
> likley not the sum of our Solar System, but rather a smattering of a few
> regions of the Solar System. We have samples from Mars, the Moon, and the
> Asteroids, that accounts for about a 10th of the mass of our solar
> system, not including the Sun. What about other moons, comets,planets,
> and object coming into our Solar System from somewhere else in the
> galaxy? That is my question, and I wanted to share it with the members of
> this list.
>         No one person can ever say they know for sure that we live in a
> stable system, and this applies to meteorites as well. Who's to say what
> is a meteorite, if we may have samples from such possibly diverse
> sources? I am NOT saying anything can be a meteorite, what I am saying is
> that, we should always be openminded, to what could be out there.
> Investigate all rocks that may be meteorites till we are satisfied they
> are, or are not. When we do this we may allow ourselves to discover
> something new, and unique.
> 
> Frank Stroik
k,,
Dear Frank,

Bravo again.  I think that at this point, we need to be open-minded
about what is or is not a meteorite. Also, I think for most of us
amateurs, we would rather be told the truth.  i.e. If it is a meteorite
or if not.  Is that so much to look for?  Thanks again.

Larry
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