Energetic Electron lensing of Ganymede’s Magnetic Field observed by the Juno Spacecraft’s Advanced Stellar Compass

Abstract

<p>The micro Advanced Stellar Compass (µASC), an attitude reference for the Juno Magnetic Field investigation, also continuously monitors high energy particle fluxes in Jupiter’s magnetosphere. The µASC camera head unit (CHU) shielding is sufficient to stop electrons with energy <15MeV. By recording the number of particles that penetrate µASC CHU shielding and deposit energy in the CCD sensor, the µASC functions as an energetic particle sensor with a detection threshold well above that of the Juno Energetic Particle Detector Instrument (JEDI) flown for that purpose. Radiation data gathered by the µASC is used to monitor the radiation environment of Jupiter and mapping of the trapped high energy particles. Comparison of the particle population around Jupiter with individual perijove particle observations reveals disturbances when Juno is traversing Ganymede’s M-shell. We present highly energetic electrons interaction with Ganymede’s magnetic field, magnitude and extend of the particle depletion associated with the Ganymede interaction.</p>