Giant Planets: Linking Internal Structure with Formation

Abstract:

The internal structures of Jupiter and Saturn are not perfectly known. However, accurate measurements of their gravitational fields provide information on their bulk compositions and their depth dependence. In particular, interior models are used to determine Jupiter and Saturn's core masses and heavy element enrichment. The inferred compositions depend not only on the equations of state of hydrogen and helium but also on some structure model assumptions such as the heat transport mechanism, number of layers, rotation profile, etc. New measurements of the physical and chemical properties of Jupiter and Saturn are expected from the Juno and Cassini Proximal missions, and we therefore expect great improvement in our understanding of the internal structures of these planets and for this reason it is crucial to identify the model uncertainties. Once the internal structures of the planets are determined they can be linked to formation and evolution theories. I will present recent developments in interior modeling, discuss the relation between the primordial internal structure of giant planets and their formation mechanism, and show how formation and evolution can be linked to the present time internal structure. Since Jupiter and Saturn are often used as calibrators for giant exoplanets, a more complete understanding of Jupiter and Saturn provides great leverage for modeling gas giant planets around other stars.