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Interior of Ceres

Interior of Ceres
Interior of Ceres This artist's concept summarizes the picture scientists have formulated of Ceres' interior structure thanks to Dawn's exploration. Unlike small chunks of rock, including typical asteroids, the dwarf planet is so large and massive that it differentiated, a geological term indicating it separated into distinct layers, with different density and different composition at different depths. It is not yet known whether there is a dense core, like the iron-nickel center of Earth or of Vesta. The green part, the mantle, is principally hydrated rocks, which are minerals that incorporate water (such as clay). The brighter green layer is a sort of transition zone at the top of the mantle, 40 miles (60 kilometers) or more thick. It has not only hydrated rocks but perhaps also briny water, making a sort of mud. Surrounding that is the crust, which is only half the density of the mantle. This outermost layer, going from the surface down to about 25 miles (40 kilometers), consists of a mixture of rock, ice, salt, more hydrated minerals and clathrates. A clathrate is like a molecular cage of water that imprisons a gas molecule. Clathrates are often found on the ocean floor on Earth. They are much stronger than ice at the same temperature and give the crust much greater strength than it would otherwise have. Full image and caption. NASA / JPL-Caltech / UCLA / MPS / DLR / IDA