Orateur
Description
The magnetospheres of giant planets are governed by the interplay of these planets’ fast rotation,
the solar wind and inner plasma sources. In the Saturn and Jupiter magnetospheres, plasma is mainly
produced by the ionization of neutral gas tori at the radial location of active moons: Io at Jupiter
and Enceladus at Saturn. The mechanisms by which these moon-associated plasma sources are re-
distributed throughout these magnetospheres involve both plasma motions and magnetic flux tube
exchanges which can be modeled as fairly axisymmetrical in the inner regions of the system. These motions are coupled to the rotation of the planets through electric current systems
originating in the equatorial plasma disk and closing into their upper atmosphere and ionosphere. Plasma additionally undergo a second type of large-scale convection due to the interaction between the magnetosphere and the Solar Wind, inherently asymmetrical in azimuth.
Based on the magnetosphere-ionosphere coupling approach, we build an analytical model of axisymmetrical plasma transport and solar-wind-driven convection in the gas giant magnetospheres. The specificity of each system is discussed as well as the way forward for modelling work.