NASA Perseverance detects organics as Brazilian lagoon bacteria model Mars habitability

Researchers at the Universidade de São Paulo’s AstroLab have been studying the extremophilic bacterium Staphylococcus nepalensis, isolated from the hypersaline Brejo do Espinho lagoon in Rio de Janeiro. The organism’s ability to survive rapid changes in salinity and very high salt concentrations makes it a useful analogue for testing the survivability of microbes in the intermittent brines that may form on the Martian surface, where perchlorate salts are hygroscopic and can lower freezing points.

Meanwhile, NASA’s Perseverance rover, using its SHERLOC instrument, identified macromolecular carbon‑rich compounds in rocks of the Bright Angel formation near Jezero crater. The complex organics, along with associated carbonates and sulfates, suggest ancient water‑rich environments and chemical conditions that could have supported life, although the rover cannot determine whether the compounds are of biological or abiotic origin. Together, the Earth‑based bacterial study and the Martian organic detections provide complementary insights into the potential for life to exist—or have existed—under the harsh conditions of Mars.