Evidence for a subsurface ocean on Europa

High-resolution Galileo spacecraft images of Jupiter's moon Europa indicate the existence of mobile 'icebergs.' There is convincing evidence for the existence of liquid water at shallow depths below the surface, either now or at some point in the past. It appears that the mobile layer, either water or warm ice, is or was widespread, and not limited to the small area studied. The processes that have disrupted Europa's plains are almost certainly continuing at present.