How do the properties and location of Callisto differ form those of the other Galilean moon?

Callisto, the outermost of the Galilean moons, differs from its siblings—Io, Europa, and Ganymede—in several key ways. It has a heavily cratered, icy surface indicating a lack of geological activity, unlike Io's volcanic activity or Europa's potential subsurface ocean. Callisto is also less dense and has a higher proportion of water ice, while Ganymede is the largest moon and has a magnetic field. Its location further from Jupiter means it experiences less tidal heating compared to the other moons, contributing to its more stable and ancient surface.