Potential Biosignature Detected on Mars, Sparking New Hope for Evidence of Ancient Life
JEZERO CRATER, MARS – NASA’s Perseverance rover has detected a potential biosignature within sedimentary rocks billions of years old in the Jezero Crater, a region scientists believe once held a lake, according to a study published in the journal Nature. The revelation centers around the presence of two minerals – vivianite, an iron phosphate, and greigite, an iron sulfide – which appear to have formed through chemical reactions involving organic materials in ancient mud deposits.
The finding doesn’t confirm past life on Mars,but represents a notable step in the search. Scientists believe similar reactions on earth are frequently enough driven by microbial activity, where microbes consume organic matter and produce these minerals as a byproduct. The Jezero Crater is considered a prime location to search for evidence of ancient Martian life, as rivers are thought to have flowed into the crater over 3.5 billion years ago, creating a perhaps habitable lake habitat.
Joel Hurowitz, a planetologist at Stony Brook University who led the research, explained the significance: “These reactions seem to have occurred shortly after the deposit of the mud at the bottom of the lake. On earth, reactions of this type, which combine organic matter and chemical compounds present in mud to form new minerals such as vivianitis and greigitis, are often caused by microbes activity.”
Though, Hurowitz cautioned against definitive conclusions. “However, we cannot say that it is more than a potential biosignature, because certain chemical processes can cause similar reactions in the absence of biology, and we cannot completely exclude these processes on the basis of robot data alone,” he stated.
The rover is currently collecting samples from the “Radiant angel” formation, and scientists hope that analyzing these samples – if they are eventually returned to Earth - will provide verifiable hypotheses to determine whether biological processes were responsible for the mineral formations. Hurowitz added, “subsequent research will provide us wiht a series of verifiable hypotheses making it possible to determine whether biology is responsible for the formation of these characteristics in the Bright Angel training, which we can assess by examining the sample of the Canyon sapphire if it is brought back to earth.”
