DISCOVERY OF WATER ON THE GALILEAN SATELLITES BY THE GALILEO MAGNETOMETER

摘要

During its mission around Jupiter, the Galileo spacecraft had many encounters with the four Galilean satellites, Io, Europa, Ganymede and Callisto. Magnetic field measurements taken during the encounters with the moons have shown that, except for Ganymede the moons are unmagnetized. However, all three icy moons respond inductively to the time varying Jovian background field. From this effect we are able to deduce that there have to be conducting liquid layers, or oceans, within the icy shells of these moons.