MASS-RADIUS RELATIONSHIPS IN ICY SATELLITES

Using published laboratory data for H2O ice, we have developed a modeling technique by which the bulk density, density and temperature profile, rotational moment of inertia, central pressure, and location of the rock-ice interface can all be obtained as a function of the radius, the heliocentric distance, and the silicate composition. Models of the interiors of Callisto, Ganymede, Europa, Rhea, and Titan are given, consistent with present mass and radius data. The radius and mass of spheres of ice under self-gravitation for two different temperature classes are given (103 and 77°K). Measurements of mass, radius, and I/MR2 by spacecraft can be interpreted by this model to yield substantial information about the internal structure and the ice: rock ratio of the icy satellites of Jupiter and Saturn. © 1979.