The Jovian Magnetodisc Azimuthal and Radial Fields Mapped by the Juno Spacecraft

The Jovian magnetodisc, previously modeled using in situ measurements made by the Pioneer, Voyager, and Galileo spacecraft, is a defining feature of Jupiter's magnetosphere. The magnetodisc geometry is formed by a system of azimuthal and radial currents occupying a washer-shaped disc confined near the magnetic equator and extending radially outward from Io's orbit. The Juno spacecraft's high inclination orbit provides a novel opportunity to explore the spatial components of existing models by providing magnetic field measurements well above the equator as well as at large radial distances from the planet. Magnetodisc models are constructed by performing singular value decomposition inversions to find best-fitting models by constraining the magnetodisc's radial boundaries, thickness, current density, and symmetry axis. The azimuthal current density included in previous model iterations has been augmented by the introduction of a radial current density. Both current systems are assumed to occupy the same region of space, and the out-of-phase sign reversals of the azimuthal and radial magnetic fields when crossing the magnetodisc provide the necessary boundary conditions. The magnetodisc models constructed are then discussed in the context of the models' implications on the magnetodisc stability and magnetic mapping throughout the magnetosphere.