Interiors of icy bodies in the solar system

Many bodies in our solar system may contain oceans. Jupiter's ice-coated moons (Europa, Ganymede, and Callisto) probably contain internal saltwater oceans. The more distant large and medium-sized icy moons, the icy dwarf planets, and tiny Enceladus may contain colder ammonia-water oceans. Oceans in icy satellites could be a common feature throughout the universe, while Earth's surface ocean may be the more unusual case. These interior models were developed by many geophysicists from data about the sizes, densities, and orbital characteristics of each body. Credit: Doug Ellison, Emily Lakdawalla, and Bob Pappalardo