EXPLORING EUROPA

Jupiter's moon Europa may be a habitable world. Galileo spacecraft data suggest that an ocean lurks beneath its frozen ice surface. A paucity of large craters argues for a surface only ~60 Myr old and likely recent geological activity, and magnetometry confirms that a salty ocean persists today. Europa's ocean and surface are inherently linked through tidal deformation of the floating ice shell. Tidal flexing and nonsynchronous rotation generate stresses that fracture and deform the surface to create ridges and bands. Dark spots, domes, and chaos are probably related to tidally driven ice convection and partial melting within the ice shell. Surface salts, sulfuric acid, and CO2 have been inferred from near infra-red observations. Europa's geological activity and probable mantle contact permit the chemical “ingredients” necessary for life to be present within the satellite's ocean. Astonishing geology and high astrobiological potential make Europa a top priority for future spacecraft exploration, with a primary goal of assessing its habitability.