Abstract
We present an application of the latest UCL-AGA magnetodisc model
(MDISC) to the study of the magnetic and plasma conditions in the
near-Ganymede space. By doing this, we provide a comparison with
measurements from Juno’s most recent flyby of the Jovian moon, perijove
34 (PJ34). We find good agreement between the model results and the
magnetometer data, pointing towards a hot plasma index value $K_h =
\SI{2.719(24)e7}{\pascal\,\meter\,\tesla^{-1}}$
and an effective magnetodisc radius $r_{\text{max}}
= \SI{79.5(11)}{}$ Jupiter radii for the Jovian
magnetosphere, for the duration of the trajectory, suggesting a
configuration with middling levels of expansion. We also predict the
plasma conditions observed by Juno during the same flight-path, as well
as the typical conditions over the orbit of Ganymede, with the magnetic
and hot plasma pressures assuming dominant roles. Finally, these results
are compared with functional fits of a compilation of Galileo flyby data
obtained in the vicinity of Ganymede’s orbit, suggesting Juno
experienced somewhat similar conditions, despite a systematic
overestimation in magnetic field intensity in the near-Ganymede space.