The effect of differential rotation on Jupiter's low-degree even gravity moments

Y. Kaspi , T. Guillot (1) , E. Galanti , Y. Miguel (1) , R. Helled , W. B. Hubbard , B. Militzer , S. M. Wahl , S. Levin , J. E. P. Connerney , S. J. Bolton

1 OCA - Observatoire de la Côte d'Azur

The close-by orbits of the ongoing Juno mission allow measuring with unprecedented accuracy Jupiter's low-degree even gravity moments J₂, J₄, J₆, and J₈. These can be used to better determine Jupiter's internal density profile and constrain its core mass. Yet the largest unknown on these gravity moments comes from the effect of differential rotation, which gives a degree of freedom unaccounted for by internal structure models. Here considering a wide range of possible internal flow structures and dynamical considerations, we provide upper bounds to the effect of dynamics (differential rotation) on the low-degree gravity moments. In light of the recent Juno gravity measurements and their small uncertainties, this allows differentiating between the various models suggested for Jupiter's internal structure.

Mots clés: Jupiter; Juno; differential rotation; atmospheric dynamics; gravity moments; gravity

Domaines: Planète et Univers [physics]

Y. Kaspi, T. Guillot, E. Galanti, Y. Miguel, R. Helled, et al.. The effect of differential rotation on Jupiter's low-degree even gravity moments. Geophysical Research Letters, 2017, 44, pp.5960-5968. ⟨10.1002/2017GL073629⟩. ⟨insu-03689225⟩