Does Europa have an underground ocean?

Answer 1

Current science suggests that there is a liquid water ocean underneath the icy crust of Europa. An ocean was initially postulated after Voyager imaging of Europa revealed a young surface that has undergone recent resurfacing. Galileo magnetometer and imaging results have supported the existence of a subsurface ocean. Europa's fiery neighbor, Io, has volcanism driven by tidal forces, creating by the pushing and pulling of the moons elliptical orbits by massive Jupiter. Similar forces acting farther out on Europa are presumed to be creating the cracks and disruptions on the surface, and maintaining the ocean beneath. Plans are being reviewed by NASA for future missions to specifically study Europa and possibly even land on its surface.