Perseverance’s radar revealed ancient subsurface river delta on Mars

NASA's Perseverance rover's ground-penetrating radar (RIMFAX) has detected what appears to be an ancient river delta buried tens of meters beneath the surface of Jezero Crater's Margin unit. The subsurface feature, older than the visible Western Delta, lies within carbonate-rich deposits known for preserving biosignatures on Earth. Scientists consider it a promising location to search for signs of ancient microbial life on Mars.