Interiors of the Giant Planets

Abstract

From our position as inhabitants of a rather insignificant rock orbiting close in \nto the Sun, there is an inevitable tendency to think of the giant planets (Jupiter, \nSaturn, Uranus, and Neptune) as being qualitatively similar. One of the major \nadvances in our understanding of the giant planets in recent years has been the \nrealization that this supposed similarity is superficial. With our previously \nblurred vision replaced by the focused spotlight of flyby spacecraft, and with \nrecent theoretical and experimental advances in the properties of materials at \nhigh pressure, the individuality of these planets has emerged. Jupiter and \nSaturn, once thought to be very similar, now emerge as having substantially \ndifferent compositions, evolutions, and structures. Uranus and Neptune still \nappear to be similar because our vision is still blurred (flybys not having taken \nplace yet), but previous experience suggests that we should not be surprised \nif important differences exist.