Theory of Figures to the Seventh Order and the Interiors of Jupiter and Saturn

Abstract Interior modeling of Jupiter and Saturn has advanced to a state where thousands models are generated that cover the uncertainty space many parameters. This approach demands fast method computing their gravity field shape. Moreover, Cassini mission at ongoing Juno delivered gravitational harmonics up J 12 . Here we report expansion theory figures, which is for shape computation, seventh order (ToF7), allows computation 14 We apply three different codes compare accuracy using polytropic models. ToF7 interior in conjunction with CMS-19 H/He equation state. For Jupiter, find 6 best matched by transition from an He-depleted He-enriched envelope 2–2.5 Mbar. However, atmospheric metallicity reaches 1 × solar only if adiabat perturbed toward lower densities, or surface temperature enhanced ?14 K Galileo value. Our imply largely homogeneous-in-Z 1.5–4 atop small core. Perturbing yields profiles extended, heavy-element-enriched deep (diffuse core) out 0.4 R Sat , as Jupiter. Classical compact, dilute, no core possible long enriched heavy elements. Including thermal wind fitted observed speeds, representative consistent all n values.