LASP Magnetosphere Seminars

Abstract

Energetic electron precipitation links Jupiter’s magnetosphere to its atmosphere by transferring trapped particle energy into the upper atmosphere. While the main auroral oval is well studied, the contribution from regions equatorward of the oval, including the diffuse aurora, remains less well quantified.

In this seminar, I present a statistical analysis of energetic electron precipitation (30 keV–1.2 MeV) using in-situ measurements from Juno’s JEDI instrument. Combining particle observations with magnetic field line tracing (JRM33), loss cone properties and atmospheric energy input are derived across the magnetosphere. Focusing on M-shells 2–30, precipitating energy flux is quantified and its dependence on magnetic local time and System III longitude is examined. 

The results show that precipitation equatorward of the main auroral oval contributes significantly to Jupiter’s atmospheric energy budget and can rival or exceed the main auroral power. Magnetic local time and longitudinal asymmetries are observed, linked to hemispheric differences in magnetic field structure and ultimately loss cone geometry. These findings establish diffuse auroral precipitation as a major pathway for atmospheric energy deposition at Jupiter.