Juno observations of large-scale compressions of Jupiter's dawnside magnetopause

Abstract

We investigate the structure of Jupiter's dawnside magnetopause using observations obtained by particle and fields instrumentation on the Juno spacecraft. Characterization of Jupiter's magnetopause is critical for the understanding of mass and energy transport between the solar wind and the magnetosphere. We find an extended magnetopause boundary layer (MPBL) during a magnetopause crossing on 14 July 2016. This thick MPBL, in combination with a large magnetic field component normal to the magnetopause boundary, suggests that strong magnetospheric compression enhances mass transport across the magnetopause via magnetic reconnection. We further identify ~2 h increases in the total magnetospheric pressure adjacent to the magnetopause on 14 July 2016 and 1 August 2016. These large-scale structures provide evidence of focused energy transport into the magnetosphere via magnetohydrodynamic structures.