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There are compelling structures in a slab of sedimentary Mars rock, but their discovery alone won't prove there was ancient life on Mars.

Time and time again, as we carefully scrutinize the amazing high-resolution imagery flowing to Earth from NASA's Mars rover Curiosity, we see weird things etched in Martian rocks. Most of the time our brains are playing tricks on us. At other times, however, those familiar rocky features can be interpreted as processes that also occur on Earth.

Now, in a paper published in the journal Astrobiology, a geobiologist has related structures photographed by Curiosity of Martian sedimentary rock with structures on Earth that are known to be created by microbial lifeforms. But just because the structures look like they've been formed by microbes on Mars, does it mean that they were?

Microbially Induced Sedimentary Structures on Mars?

SOURCE: Seeker.com



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The image in question was snapped by Curiosity of the Gillespie Lake outcrop situated in the Yellowknife Bay area of Gale Crater that the rover arrived at on Dec. 17, 2012, on sol 125 of its mission. It was soon realized that the Gillespie Lake rock is sedimentary sandstone, formed when Mars possessed surface water. As such, there are many likenesses between the rocks found in Yellowknife and sedimentary rocks on Earth. For example, the layering of sedimentary rock and conglomerations contained within these layers led NASA scientists to realize that Curiosity is exploring an ancient lake bed.


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In her analysis, Noffke is keen to emphasize that she hasn't found proof of ancient Mars life, only that her hypothesis provides a compelling explanation for the formation processes behind the shapes in the surface of Mars sedimentary rock.

Paper: Ancient Sedimentary Structures in the <3.7 Ga Gillespie Lake Member, Mars, That Resemble Macroscopic Morphology, Spatial Associations, and Temporal Succession in Terrestrial Microbialites

“All I can say is, here's my hypothesis and here's all the evidence that I have," said Noffke in an Astrobiology Magazine article, “although I do think that this evidence is a lot."

There have been countless claims pointing to evidence of ancient life on Mars, many of which have since been proven to be, at most, wishful thinking, but this new study has garnered some cautious praise from planetary scientist Chris McKay, of NASA's Ames Research Center and an associate editor of Astrobiology.

SOURCE: Seeker.com