[meteorite-list] Temperature of meteorites

From: almitt2 at localnet.com <almitt2_at_meteoritecentral.com>
Date: Tue, 23 Nov 2010 07:00:11 -0500
Message-ID: <20101123070011.u2qgfn3akym8ww08_at_webmail.localnet.com>

Greetings listees,

ahhh the hot/cold debate rears it's head again. I appreciate Bernd's
list of falls that seem to indicate warm more so than cold but there
are many factors to consider when compiling data. In Bernd's list, how
many of these warm specimens were observed by laymen?? Often there are
other factors to consider and layman's observations can be often wrong.
If a black specimen sits for very long in the sunlight it will absorb
warmth and appear warm or hot.

Things to consider, Fall dynamics. The space shuttles build up a lot of
high heat during decent through the atmosphere. Shuttles have to cool
for a while after landing. Meteoroids, depending on their fall speed,
only pass through the atmosphere for a short period of time (seconds
before dark flight) and don't have suffiecent time to build up heat.
The ablating process often removes the molten material as the object
falls keeping the specimen more or less at cold space temperature.

Catching up or head on collision with Earth effects speed and
temperature and fall dynamics. Spinning or stable flight (possible
oriented specimen) affects temperature. Size of specimen and retention
of cold from space.

One thing for certain when thinking about the hot/cold debate. If
meteoroids are heated up molten when they fall, then the chemistry
would be altered and isotopes reset. Most meteorites don't have high
heat alteration from falls or our ability to study them would be
impossible. The age would be reset from the heating. The study of
meteorites is the study of un-altered specimens from our solar systems
past!!

I tend to be a cold when they land believer but think a few can come
down oriented and there is time for them to absorb some heat from the
fall. Nininger investigated several falls seen by laymen that were
frosted over but he was efficient at determaining facts based on the
story tellers.

There are a lot more considerations and facts about falls that are
probably still not understood at this time. Fall dynamics are difficult
to study unless you have an expert with equipment the second the fall
occurs at the site when it happens.

My hot and cold worth.

--AL Mitterling
Mitterling Meteorites
Received on Tue 23 Nov 2010 07:00:11 AM PST