Jovian moon Europa may be undergoing plate tectonics

Nature : Images from NASA’s Galileo spacecraft, which orbited Jupiter from 1995 to 2003, indicate that one of its moons—Europa—may be undergoing a system of plate tectonics similar to that of Earth. According to a new study published in Nature Geoscience, ridges and bands covering the moon’s surface suggest that icy crustal plates a few kilometers thick may be sliding around on warmer, more fluid ice below, which sits above a hidden, watery ocean. As two plates slide together, some of the ice is subducted, melted, and returned to the interior, while new ice forms at the surface. To better understand the extent of the subduction, however, higher-resolution images will be needed. NASA is currently seeking proposals for such a Europa mission. If the moon is undergoing widespread tectonic activity, it would allow the recycling of salts, minerals, and possibly even microbes between its ocean and its surface.