NASA’s Perseverance rover has been exploring Jezero Crater on Mars for the past three years, offering the most detailed look yet at a place once filled with water. From orbit, scientists had already spotted signs of clays and carbonates – minerals that form in watery environments. Now, thanks to Perseverance’s close-up work, researchers are uncovering new details about Mars’ ancient chemistry and what it might mean for the planet’s potential to host life long ago.

Early in its mission, Perseverance studied volcanic rocks near its landing site, then made its way toward a fan-shaped river delta. Along the way, it confirmed the presence of clays and carbonates and discovered unusual nodules of iron phosphate and iron sulfide in mudstone. These minerals are important because they often form in connection with water and, on Earth, sometimes biology. What’s more, they appeared more often in places where organic molecules were also detected, suggesting that organics may have played a role in chemical reactions on early Mars.

These reactions, called redox reactions, occur when minerals gain or lose electrons. On Earth, such processes can provide energy for microbes, and in the past, they may have been important for life’s early chemistry. Perseverance’s instruments, including SHERLOC, have shown that organic compounds were indeed present in Jezero, raising the possibility that Mars once had the right mix of minerals, water, and chemistry to support prebiotic processes.

Meanwhile, scientists are also improving how they study Mars from orbit. The CRISM instrument aboard the Mars Reconnaissance Orbiter has mapped minerals across Jezero Crater, but its data can be distorted by Mars’ atmosphere and instrument quirks. Researchers have recently developed advanced correction methods and even used artificial intelligence to create the clearest mineral maps of Mars yet. These new tools reveal small deposits of clays, carbonates, and other minerals that were previously hidden in the data.

Together, Perseverance’s discoveries on the ground and sharper orbital views from space are painting a richer picture of Mars’ watery past. The rover has already collected samples from promising sites, and once they return to Earth, scientists will be able to study them in detail – potentially uncovering new clues about whether life ever had a foothold on the Red Planet.

For more details, read the full article by SETI Institute.