Ice Giant Magnetospheres

The Ice Giant Magnetospheres provide some of the most interesting natural laboratories for studying the influence of large obliquities, rapid rotation, highly asymmetric magnetic fields, and large Alfvénic and sonic Mach numbers on magnetospheric processes. Uranus is subjected to extreme seasonal variations resulting from the nearly 98° tilt of its rotation axis. At both Uranus and Neptune, the solar wind-magnetosphere interaction varies dramatically on diurnal and seasonal timescales due to the apparent offset and large tilt of the dipole field. With in situ observations limited to a single encounter by the Voyager 2 spacecraft, a growing number of analytical and numerical models have been put forward to characterize ice giant magnetospheres and test hypothesis related to magnetospheric boundary layers, the solar wind interaction, the formation of the radiation belts, understanding charged particle precipitation, aurora, and energy deposition to the atmosphere, and quantifying potential plasma sources and the distribution of plasma observed. Yet despite these recent studies, many questions regarding the observations of the Ice Giant magnetospheres remain unanswered. This has led to great community interest in revisiting these distant worlds, with the Decadal Survey placing the Uranus Orbiter and Probe (UOP) as the highest flagship mission priority, and the Planetary Mission Concept Study Neptune Odyssey receiving tremendous support as well. In this tutorial I will describe the current understanding of the ice giant magnetosphere, as well as the key magnetospheric science questions motivating the UOP mission.