loading page

A Juno-era View of Electric Currents in Jupiter's Magnetodisk
  • Z.-Y. Liu,
  • Michel F. Blanc,
  • Qiu-Gang Zong
Z.-Y. Liu
Peking University
Author Profile
Michel F. Blanc
IRAP, CNRS-UPS-CNES

Corresponding Author:[email protected]

Author Profile
Qiu-Gang Zong
Peking University
Author Profile

Abstract

Recent observations from Juno provided a detailed view of Jupiter’s magnetodisk, including its magnetic fields, waves, plasmas and energetic particles. Here, we contribute to Juno results by determining the electric currents threading the magnetodisk and their coupling to field-aligned currents (FAC) in the midnight-to-dawn local time sector. We first derive from Juno magnetic field data the spatial distributions of the height-integrated radial (Ir) and azimuthal (Ia) currents in the magnetodisk, and then calculate the FACs from the divergence of the two current components. The Ir-associated FAC, Jr, flows into and out of the magnetodisk at small and large radial distances, respectively, approximately consistent with the axisymmetric corotation enforcement model. On the other hand, Ia decreases with increasing local time everywhere in the local time sector covered, indicating an additional FAC (Ja) flowing out of the magnetodisk. From Ia and Ja, we conclude that the influence of the solar wind, which compresses the dayside magnetosphere and thus breaks the axisymmetry of currents and fields, reaches deep to a radial distance of at least 20 Jupiter radii. Our results provide observational constraints on Jupiter’s magnetosphere-ionosphere-thermosphere coupling current systems, on their relation to the main auroral emission and on the radial mass transport rate in the magnetodisk, which we estimate to be close to ~1500 kg/s.
25 Feb 2023Submitted to ESS Open Archive
27 Feb 2023Published in ESS Open Archive