James G wrote:

One thing I have never seen addressed or maybe I missed it when there
was a big hub-bub about it, but...

How do they *know* these meteorites actually came from Mars?

Even if they have the right spectral and chemical composition, a rock
is a rock isn't it?

TIA,


IIRC it was due to the composition of gases that were trapped in the
rock, and which were a dead-on match for the Martian atmosphere as
analyzed by the Viking landers.

Pat