A Tale of Two Planets: Dilute Cores in Jupiter and Saturn from In Situ Spacecraft Observations

The interiors of planets contain clues that inform us about the early processes that led to the formation of the solar system. Until lately, gas giant planets were traditionally considered to consist of a compact core of rocky material confined by an envelope of H and He fluid. Recent NASA missions Cassini (Saturn) and Juno (Jupiter) have questioned this traditional picture. Instead of a compact core, the recent missions observe a dilute core defined by a region with a chemical gradient that extends radially over tens of thousands of kilometers. In this talk, I will present evidence favoring dilute over compact cores in gas giant planets and discuss implications for planet formation and evolution. I will put particular emphasis in my own contributions to developing a theory of dynamical tides capable of uncovering the interiors of fluid bodies in the solar system; this includes the gas giant planets and icy satellites with global oceans. I will end this talk discussing potential applications of dynamical tides to the study of icy satellites Europa and Ganymede from future missions Europa Clipper and JUICE, respectively.

Speaker: Benjamin Idini, UC Santa Cruz