Searching for life has always been a cornerstone of NASA’s mission on Mars. One geobiologist has found some striking similarities between a picture of Martian sedimentary rock and rock shaped by microbial life on Earth.
Nora Noffke, a geobiologist at Old Dominion University in Virginia, spotted the similarities in a picture taken a couple of years ago by NASA’s Curiosity rover.
Noffke has been studying microbial structures for the past 20 years. So, she knows a thing or two about how microbial fossils look on rocks.
Microbial mats could have shaped the rocks in the image above. Imagine sheets of microbes covering rocks. These then fossilize and can be seen on the rocks.
Did that happen on Mars? Noffke reasons that if Mars did harbor microbial life in the past, it probably looked similar to that found on Earth.
A sketch overlay showing the various structures possibly formed by microbial mats
Noffke is quick to point out she hasn’t found proof of life in Mars’ past.
While it’s not ironclad proof of life on Mars, Noffke’s study is drawing the eyes of NASA.
“I’ve seen many papers that say ‘Look, here’s a pile of dirt on Mars, and here’s a pile of dirt on Earth,’” says Chris McKay, a planetary scientist at NASA’s Ames Research Center and an associate editor of the journal Astrobiology. “And because they look the same, the same mechanism must have made each pile on the two planets.’”
McKay praises how detailed Noffke’s paper is and says that is “why it’s the first of its kind published in Astrobiology.”
Bringing a sample of the rock back from Mars would prove if Noffke is right. But, that won’t be happening anytime soon.
What else could it be? Noffke says the features on the Martian rock could have been produced by erosion.
“But if the Martian structures aren’t of biological origin,” Noffke says, “then the similarities in morphology, but also in distribution patterns with regards to MISS on Earth would be an extraordinary coincidence.”
MISS, microbially-induced sedimentary structures, are found in shallow water around the world an in ancient rocks.
Noffke does make a compelling case for potential life in Mars’ past. Now, we just need to get some people on Mars, or a rock back to Earth, to test her hypothesis.