Perseverance Rover Detects Buried Ancient River Delta on Mars

NASA's Perseverance rover has uncovered evidence of an ancient river delta buried deep beneath the surface of Mars in Jezero Crater, offering some of the earliest indications yet of liquid water flowing on the Red Planet billions of years ago. The discovery, detailed in a study published in the journal Science Advances, points to a water-rich environment that predates known surface features and could have supported microbial life.

Using its Radar Imager for Mars' Subsurface Experiment, or RIMFAX, the rover detected layered sedimentary deposits characteristic of a delta, where rivers once deposited sediment into a larger body of water like a lake. Over 250 Martian days from September 2023 to February 2024, Perseverance traversed about 3.8 miles within the 30-mile-wide Jezero Crater in Mars' northern hemisphere. The instrument sent radar pulses into the ground, mapping geological structures up to 115 feet underground and revealing sloping layers, channels, and eroded surfaces indicative of flowing water.

Researchers dated the buried delta to between 3.7 and 4.2 billion years ago, placing it early in Mars' history, which began around 4.5 billion years ago. This formation predates...