Data from NASA’s Mars Perseverance rover have shown that rocks recently discovered in Jezero crater are mudstones containing organic carbon. The findings, published in Nature, suggest these mudstones underwent chemical changes that left behind unusual textures in the rock, which may be potential biosignatures.
The research is led by Joel Hurowitz, PhD, Associate Professor in the Department of Geosciences at Stony Brook University. The team has been working with data collected since Perseverance landed on Mars in 2021. Their aim is to study early Martian geology and gather samples for possible return to Earth.
When Perseverance entered the western edge of Jezero crater, it examined mudstone outcrops called the Bright Angel formation. The Mars 2020 science team conducted a detailed analysis and found carbon matter as well as minerals like ferrous iron phosphate and iron sulfide.
While the researchers do not claim to have found fossilized life on Mars, they believe these rocks contain features that could have formed through biological processes—a potential biosignature. A potential biosignature is any feature or substance that might have been created by past life but also could form without life present. The team stresses that more information is needed before drawing conclusions about whether microbes played a role in forming these features.
“These mudstones provide information about Mars’ surface environmental conditions at a time hundreds of millions of years after the planet formed, and thus they can be seen as a great record of the planetary environment and habitability during that period,” says Hurowitz.
“We will need to conduct broader research into both living and non-living processes that will help us to better understand the conditions under which the collection of minerals and organic phases in the Bright Angel formation were formed,” he explains.
The researchers plan to continue studying these rocks and their characteristics. They state: “conclude that analysis of the core sample collected from this unit using high-sensitivity instrumentation on Earth will enable the measurements required to determine the origin of the minerals, organics and textures it contains.”