[meteorite-list] STONE Artificial Meteorite Experiments wasArtificial Lunar Meteorites?

From: Mr EMan <mstreman53_at_meteoritecentral.com>
Date: Fri, 20 Mar 2009 03:57:38 -0700 (PDT)
Message-ID: <597645.652.qm_at_web55202.mail.re4.yahoo.com>

> 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.
Received on Fri 20 Mar 2009 06:57:38 AM PDT