Pay dirt

Pay dirt
Pay dirt In May 2007, Spirit churned up pay dirt as she dragged her broken wheel in an area around Home Plate. When Steve Ruff had the robot check it out with the mineral detecting Mini-TES and the scientists reviewed her data, it turned out to be near pure opaline silica. This unexpected discovery of concentrated silica deposits and Ruff’s subsequent research indicate that there were once hot springs or steam vents at Home Plate site, which could have provided favorable conditions for microbial life. “It was one of the most important findings by either rover,” Squyres said. NASA / JPL-Caltech / Cornell / ASU