NASA finds traces of ancient river delta beneath Martian surface

NASA’s Perseverance rover has uncovered subsurface remains of an ancient river delta on Mars using ground-penetrating radar, providing some of the oldest evidence of water on the planet. The formations lie about 35 metres below the surface in Jezero Crater, where the rover has travelled more than six kilometres.

Scientists have identified layered sediments and eroded surfaces typical of a delta environment, formed when a river flows into a larger body of water. The delta is estimated to have formed between 3.7 and 4.2 billion years ago, relatively soon after Mars itself formed. According to the researchers, it predates the nearby West Delta.

The data were collected by the RIMFAX instrument, which sends radar pulses into the subsurface and enables three-dimensional mapping. The findings are based on measurements gathered between September 2023 and February 2024.

Scientists believe that Jezero Crater was once flooded and contained a lake fed by rivers. Such an environment may have been suitable for preserving biological signatures – evidence of past life.

The growing body of evidence for the ancient presence of water suggests that Mars once had a denser atmosphere and a warmer climate. The Perseverance rover has been exploring the area since 2021.

(reuters, max)