M‐Shell and Local Time Variability of the Electron and Magnetic Environments at the Orbit of Callisto as Observed by the Juno and Galileo Missions

作者：Thomas Le Liboux, Nicolás André, R. Modolo, Quentin Nénon, A. Seves, J. Rabia, Mathias Rojo, A. Kamran, Zhi‐Yang Liu, François Leblanc, Michel Blanc, P. Louarn, E. Penou, Daniel Santos‐Costa, F. Allegrini, R. W. Ebert, R. J. Wilson, J. R. Szalay, C. Paranicas, G. Clark, F. Bagenal, O. Mousis, J. E. P. Connerney, S. J. Bolton · 发表于：Journal of Geophysical Research Space Physics · 年份：2025 · DOI：10.1029/2025ja033829 · 被引用次数：1 · 研究领域：Astro and Planetary Science、Ionosphere and magnetosphere dynamics、Solar and Space Plasma Dynamics

Abstract Jupiter's moon Callisto orbits in a highly variable magnetospheric environment depending on its position relative to the Jovian current sheet. The Juno and Galileo missions have visited the Jovian magnetosphere and crossed Callisto's orbit several times in a variety of configurations, providing an opportunity to better characterize Callisto's orbital environment. The aim of this work is to characterize the variability of Jupiter's magnetospheric environment properties at Callisto's orbit. After identifying the time intervals during which both missions crossed the moon's orbit, Juno's charged particle data from the Jupiter Energetic Particle Detector Instrument and the Jovian Auroral Distributions Experiment are combined to build composite spectra of the electron differential fluxes and derive the electron density and pressure. Based on these observations, we provide empirical models of the energy spectrum of the electron flux for different positions. The electron densities and pressures estimated from our composite energy spectra vary from 0.2 cm −3 and 0.1 nPa, respectively, at the center of the current sheet to 0.009 cm −3 and 0.004 nPa, respectively, outside. We compare these observations with those obtained by the Energetic Particles Detector onboard Galileo, which reveal an additional variation of electron fluxes with local time, possibly due to a variation of the current sheet thickness. A similar comparison of magnetic field observations with the latest magnet...