NASA's Perseverance Rover Finds Carbon on Martian Rock Surface

NASA's Perseverance rover has spent five years traversing Jezero Crater looking for chemical leftovers of processes at work on Mars billions of years ago. The rover has found organic carbon, but mostly inside rocks that had to be drilled or abraded to expose it. At an outcrop on the edge of an ancient river channel named Neretva Vallis, Perseverance detected complex macromolecular carbon sitting right on the rock's surface.

"To our knowledge, that's the shallowest detection of organic matter on Martian surface to date," said Ashley E. Murphy, a researcher at the Planetary Institute in Tucson, Arizona, and lead author of the study of the rock, which was found at a site called Bright Angel. On Earth, this much macromolecular carbon usually suggests a biological origin.

But to learn what this Bright Angel carbon is and where it came from, we might need to bring samples back to Earth. The detection of Bright Angel carbon came from SHERLOC (Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals), a UV Raman spectrometer fitted on Perseverance's robotic arm. SHERLOC fires a deep-ultraviolet laser at a target and reads the light that bounces back at shifted energies, a signal that enables scientists to identify specific molecular bonds.

Why this matters: The discovery of complex carbon on the Martian surface raises questions about the planet's past habitability and the origins of life. While the presence of macromolecular carbon on Earth often suggests biological activity, its presence on Mars does not necessarily imply the same. The findings highlight the need for further research, potentially through sample return missions, to understand the Martian environment and its potential for supporting life.

For developers of future Mars missions, this discovery underscores the importance of continued exploration and analysis of Martian geology. As scientists continue to study the Martian surface, they will likely uncover more secrets about the planet's history and potential for life, with implications for both the search for life beyond Earth and our understanding of the universe.