Juno Plasma Wave Observations at Ganymede
W. S. Kŭrth, A. H. Sulaiman, G. B. Hospodarsky, J. D. Menietti, B. H. Mauk, G. Clark, F. Allegrini, P. W. Valek, J. E. P. Connerney, J. H. Waite, S. J. Bolton, Masafumi Imai, O. Santolı́k, Wen Li, Stefan Duling, Joachim Saur, Corentin Louis
Abstract
The Juno Waves instrument measured plasma waves associated with Ganymede's magnetosphere during its flyby on 7 June, day 158, 2021. Three distinct regions were identified including a wake, and nightside and dayside regions in the magnetosphere distinguished by their electron densities and associated variability. The magnetosphere includes electron cyclotron harmonic emissions including a band at the upper hybrid frequency, as well as whistler-mode chorus and hiss. These waves likely interact with energetic electrons in Ganymede's magnetosphere by pitch angle scattering and/or accelerating the electrons. The wake is accentuated by low-frequency turbulence and electrostatic solitary waves. Radio emissions observed before and after the flyby likely have their source in Ganymede's magnetosphere.