Okay, you find a rock on a glacier, why would someone conclude that it came from Mars.?

Question

Physical description, chemical composition, Martian barcode ?

Answer 1

Why Mars? Why not just a meteorite flying in outer space? Why not glacial till?

Answer 2

No one would conclude that it came from Mars without doing a lot of tests to compare the mineral makeup and structure with the local rocks.  If it doesn't look like the local rocks, then they might conclude that it came from outer space.  Then they would compare it to what are believed to be the mineral content and structure of Martian rocks.

Glaciers are a good place to look for meteorites because, once you get away from the edges, they don't have many rocks in them.   Also, the meteorites are cooled quickly and trapped in the ice, and kept separate from the local rocks. Therefore, any rocks you find have a good chance of being meteorites.  When meteorites hit land, they are more likely to break up and be mixed with the local rocks.

The best place to find meteorites is in Antarctica, where the ice is thousands of feet thick, and there are very few local rocks around.  Most rocks that you find near the surface ot the ice are likely to be meteorites, and many are believed to have come from Mars.

Answer 3

they do tests to see what elements make up the rock and look for any patterns in the rock or other clues that tell them about the temperatures where it came from. and they compare that to known data about rocks from mars and other celestial bodies.