Perseverance rover discovers Martian rock with possible signs of ancient life

Analysis of instruments on board the Explorer shows that The breed has qualities that fit the definition of a possible indicator of ancient life..

A special stone on Mars

The rock has chemical characteristics and structure that may They were formed billions of years ago.when the area the rover was exploring contained running waterThe research team is considering other explanations for the observed characteristics, and future research steps will be needed to determine whether ancient life is a compelling explanation.

The rock (the 22nd core sample returned by the rover) was collected on July 21, 2024, as the rover explored Earth’s northern edge. Neretva ValleyA ancient river valley 400 meters wide, cut by water that long ago rushed into the Jezero crater.

“We designed the Perseverance route to reach locations where interesting scientific specimens could potentially be found.“, said Nicola Foxassociate administrator of the Science Mission Directorate at NASA Headquarters in Washington.This trip along the Neretva River paid off because we found something we had never seen before and which will give our scientists a lot to study.“.

Multiple scans of the Cheyava waterfall performed by the SHERLOC device (Scanning the living environment using Raman scattering and luminescence for organic and chemical substances) of the rover indicate that contains organic compounds. Although these carbon-based molecules are considered the basic components of lifecan also be formed non-biological processes.

“Cheyawa Falls is the most mysterious, complex, and potentially important rock formation Perseverance has ever explored.“, said Ken Farleya research fellow with the Perseverance Project at the California Institute of Technology in Pasadena.On the one hand, we have the first convincing detection of organic material, characteristic color spots indicating chemical reactions that microbial life could use as an energy source, and clear evidence that water, essential for life, once flowed through the rock. On the other hand, we have not been able to determine exactly how the rock formed and to what extent nearby rocks could have heated the Cheyava Falls and contributed to these features.

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Other details about the 1 x 0.6 metre rock, named after a waterfall in the Grand Canyon, also intrigued the team.

How Stones Get Spots

In its search for signs of ancient microbial life, Perseverance focused on rocks that may have been created or altered by water long ago. So the team zeroed in on Cheyawa Falls.

“This is the key type of observation that SHERLOC was created for: searching for organics, as it is a critical component in the search for past life.“said SHERLOCK’s chief investigator, Kevin Handfrom NASA’s Jet Propulsion Laboratory in Southern California, which manages the mission.

along the cliff Large white veins of calcium sulfate expand.Between them are bands of material whose reddish color suggests the presence of hematite, one of the minerals that gives Mars its characteristic rusty hue.

When Perseverance looked closely at these red areas, it found that dozens of whitish spots irregularly shaped and millimeter-sized, each surrounded by a black material resembling leopard spots. The PIXL device (Planetary X-ray Lithochemistry Instrument) from Perseverance determined that these black halos contain iron and phosphate.

“These spots are a big surprise“, said David Flanneryan astrobiologist and member of the Perseverance science team at the Queensland University of Technology in Australia.”On Earth, such features of rocks are often associated with fossilized records of microbes who live underground“.

These types of stains in terrestrial sedimentary rocks can occur when chemical reactions involving hematite turn the rock from red to white. These reactions can also release iron and phosphate, possibly resulting in black halos. Reactions of this type can be a source of energy for microbes.

which explains the connection between such characteristics and microbes in the terrestrial environment.

In the scenario considered by the Perseverance science team, Cheyavsky waterfall was originally deposited as mud with mixed organic compounds that eventually become cemented into rockLater, a second episode of liquid flow penetrated cracks in the rock, forming mineral deposits that formed the large white veins of calcium sulfate visible today and caused the stains.