WASHINGTON—Core samples drilled by NASA’s Perseverance rover on the Martian surface are revealing the geology of a gaping crater scientists suspect may have harbored microbial life billions of years ago, including surprises about the nature of the rock present there.
The samples, obtained by the car-sized, six-wheeled robotic rover and stored for future transport to Earth for further study, showed that rock from four sites inside Jezero crater is igneous—formed by the cooling of molten material. The rocks also bore evidence of alteration through exposure to water, another sign that cold and arid Mars long ago was warm and wet….