Hi,
Yes, "wind faceted" (wind and sand ablation) seems to be the key feature of relevance. If you look at photos of the alleged meteorite found on Mars, it contains quite a few facets. And the ridges between the facets are very sharp. I have seen hard quartzite and flint-like rocks on deserts with the same sharply delineated features. The ventifacted chondrites, on the other hand, do not show these facets or sharp delineations. Neither does the banded iron example or the other iron meteorite from Antarctica.
As far as I know, these sharply delineated facets occur with wind and sand from a constant direction over a long period of time. And the material has to be hard and homogeneous. Consequently I wonder what a terrestrial iron meteorite would look like subjected to the same conditions? I have a new NWA iron that is otherwise round and smooth but clearly shows those lines but no facets. I'm sure it was attacked by water and by wind and sand, but how much by each I just don't know. I suppose even a solid hunk of non-meteoric iron subjected to the same conditions would answer the question. Unless the rock found on Mars is an ataxite, I would also expect that any attack (whether by acid or wind and sand) would reveal some evidence of Widmanstatten lines. I don't see any evidence of that in the Martian photograph.
So as much as I think it's a keen idea to find a meteorite on Mars, I'm not convinced. "Extraordinary claims require extraordinary evidence." So my questions are:
a) Why does the Martian rock show faceting? Does that support or detract from the claim that it is an iron meteorite?
b) Exactly what analysis was done on Mars? I have only seen the most general reports for PR purposes. Can anyone point me to a more definitive report? Do we have access to the thermal heating and dissipation data, for instance? And what else?
Cheers, Nick
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