Signs of acid fog found on Mars

The work focused on the 'Watchtower Class' outcrops on Cumberland Ridge and the Husband Hill summit, said Cole, who is an assistant professor at Ithaca College and began studying the area for her Ph.D. thesis at Cornell University.

"The special thing about Watchtower Class is that it's very widespread and we see it in different locations. As far as we can tell, it's part of the ground there," which means that these rocks record environments that existed on Mars billions of years ago.

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