what is the cause of volcanic activity on jupiter's moon io
Volcanology of Io First predicted shortly before the Voyager 1 flyby, the heat source for Io's volcanism comes from tidal heating produced by its forced orbital eccentricity.[3] This differs from Earth's internal heating, which is derived primarily from radioactive isotope decay and primordial heat of accretion.[4] Io's eccentric orbit leads to a slight difference in Jupiter's gravitational pull on the satellite between its closest and farthest points on its orbit, causing a varying tidal bulge. This variation in the shape of Io causes frictional heating in its interior. Without this tidal heating, Io might have been similar to the Moon, a world of similar size and mass, geologically dead and covered with numerous impact craters.[3]