Opportunity's meteorite shows little signs of errosion
Coming across a meteorite on Mars that is apparently iron in composition “is pretty amazing, but is consistent with Opportunity's luck…lands in a little crater with fascinating rocks exposed…then finds a meteorite,” said G. Jeffrey Taylor of the Hawaii Institute of Geophysics and Planetology at the University of Hawaii in Honolulu.
Taylor said the meteorite is perched like they are when found in Antarctica. In that case they are revealed by sublimation of the ice, after being transported a long way.
Unless it fell very recently, the meteorite on Mars was probably buried…then excavated when the surrounding dirt was removed,” Taylor speculated. “This leads to some interesting possibilities and questions.”
First, the meteorite is not weathered much, indicating dry conditions since it landed. “That is consistent with the presence of minerals that are easily altered by water, such as olivine,” he said, which would rot away in several thousand to a few tens of thousands of years -- depending on temperature -- if sitting in water.
So either Mars is very dry or the meteroite hasn't been exposed very long. It could have fallen out of the sky last month. More likely it was buried for a long time and exposed only fairly recently. I'd like to know the exact location of the meteorite in relation to the impact crater. I know it's a very very very long shot but wouldn't it be something if the heat shield impact uncovered it? :-)