Everyone these days seems to be interested in whether or not Mars has had life or even still has life. Scientists are continuing to analyze the geology and layering of Mount Sharp, and this week, a new paper published in JGR Planets reveals that the Stimson formation contains evidence of an ancient dune field. This layer is over other layers that we know were deposited in a large lake, and knowing how it was formed means that scientists can now work toward understanding the wind conditions of that particular era of Martian history.

Last time we talked about the Murray formation, which has been shown to have a back and forth climate pattern that goes between wet and dry several times. Now we’ve layered a very dry, very windy, very dusty climate over the top of that formation. It may have taken a while for Mars’ water to disappear, either into the atmosphere or underground into minerals, but when it left, it really affected the surface. If life was there, it either died out 3.5 billion years ago, or it went underground.

And another new study, this one in the journal Astrobiology, lays out the evidence for the possibility of subsurface life. This study examined the chemical composition of Martian meteorites that we have found here on Earth. Yay for free rock samples! These rocks could be representative of different parts of Mars’ crust. Per the press release: The analysis determined that those rocks, if in consistent contact with water, would produce the chemical energy needed to support microbial communities similar to those that survive in the unlit depths of the Earth.

This follows a story we covered a couple of weeks ago that showed that biofilms and other life have been found deep underground in an old gold mine, and that life is surviving without access to sunlight or oxygen. The same could hold true for Mars, giving us another avenue for finding current life on the red planet.

More Information

Imperial College London press release

“A Rock Record of Complex Aeolian Bedforms in a Hesperian Desert Landscape: The Stimson Formation as Exposed in the Murray Buttes, Gale Crater, Mars,” Steven G. Banham et al., 2021 March 30, JGR Planets

Brown University press release

“Earth-like Habitable Environments in the Subsurface of Mars,” J.D. Tarnas et al., 2021 April 15, Astrobiology