Wind-induced odd gravitational harmonics of Jupiter

Abstract

While the rotational distortion of Jupiter makes a major contribution to its lowermost order even zonal gravitational coefficients Jn with n ≥ 2, the component of the zonal winds with equatorial antisymmetry, if sufficiently deep, produces a gravitational signature contained in the odd zonal gravitational coefficients Jn with n ≥ 3. Based on a non-spherical model of a polytropic Jupiter with index unity, we compute Jupiter's odd gravitational coefficients J3, J5, J7, …, J11 induced by the equatorially antisymmetric zonal winds that are assumed to be deep. It is found that the lowermost odd gravitational coefficients J3, J5 and J7 are of the same order of magnitude with J3 = −1.6562 × 10−6, J5 = 1.5778 × 10−6 and J7 = −0.7432 × 10−6, and are within the accuracy of high-precision gravitational measurements to be carried out by the Juno spacecraft.