> Dave Gheesling wrote:
> "...Meteorites don't enter our atmosphere attached
> to spheres, and presumably that artificial contraption may
> have made for a different-than-typical result...."
> Dave
> www.fallingrocks.com

I totally agree, Dave.

Yet again I am not getting all the original post but in regard to Dave's quote 
...  This was recently raised on the list with out-of-context examples 
suggesting that fusion crust is not what colors meteorites black, Fusion crust 
does not always form, yada yada.  The example cited was the ESA experiment 
series called STONE( 1-7?). (and BioPan).(Not acronyms apparently-- just 
project names)

In acquiring knowledge there is always a risk in knowing how to Google without 
yet having fundamental understanding of the subject matter to compare and 
contrast. That is ok as we were all ignorant of the world once in our past. 
Wisdom and more knowledge are acquired in time and mediates that 
disconnect-hopefully.

STONE/BioPan was a series of experiments to ascertain effects on various 
rocks(sedimentary,metamorphic,and igneous of various chemical/mineral 
composition*) in an artificial, re-entry setting to study the survivability of 
fossils, organic chemicals and living bacterial life forms(BioPan). It was NOT 
an ablation/fusion crust experiment per se.  In fact the samples were attached 
on the shadow area behind the return capsule at a point known as the stagnation 
zone.  This is an area out of the slipstream where maximum heating is 
concentrated without full evaporating air flow**.  This design was a compromise 
to preserve the 15mm thin samples while still exposing them to maximum heating 
them to around 2000degC. Much ablation did occur however and the sample most 
resembling a meteorite was lost entirely(basalt).  The next closest sample was 
"micro-fossil infused, olivine sand" cemented together with gypsum which has a 
lower melting/disintegration point than the
 samples it held in place--much of this sample was lost as well. In all the 
coverage I was only able to locate two "sample" photos with only one having a 
before and after view.

My opinion: the experiment was an add-on to an existing mission and was rushed 
for funding approval and launch date-- like most orbital experiments. This 
resulted in an ill thought through design that most any geology/chemical 
undergrad major could predict the failures of. I'll omit specific for now.

Bottom line is, while it seems on the surface to be a "meteorite experiment" it 
was not in a strict sense. Parts were insightful and did tend to confirm what 
was already know through meteorite internal heating research. One has to glean 
from these results those which are applicable to meteorite science and to 
discard those results stemming from compromised design and the limitations of 
of an experimental package. 

Elton
 
Footnotes: 
* One rock sample was dolomite which on heating, outside a pressure vessel, 
doesn't "melt/fuse" but sublimates carbon dioxide and leaves milk of magnesia 
and quicklime behind.  No fusion crust should have been predicted and no fusion 
crust was seen-- only a white powder "film"--who'd a guessed?

The high-feldspar-containing sandstone sample did melt but the "fusion crust" 
was largely composed of the fibers from the holding fixture. Next time I 
recommend quartzite which is feldspar depleted.

**I believe there ARE implications for understanding flight mark features on 
the back of oriented meteorites as they too have stagnation zones. e.g bubbles, 
froth etc.
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