Magnetosphere-Ionosphere Coupling at Earth, Jupiter, and Saturn

Abstract:

Magnetosphere-ionosphere (M-I) coupling occurs at every planet with a substantial atmosphere and magnetic field. Field-aligned currents communicate energy and angular momentum between the two regions, often resulting in bright auroral emissions. At Earth, field-aligned currents are predominately driven by the interaction of the solar wind with the magnetosphere. In the plasma-laden magnetospheres of Jupiter and Saturn, field-aligned currents convey angular momentum from the planet to its surrounding plasma disc in an attempt to maintain rigid corotation between the two regions. I will review the drivers of and limitations to M-I coupling at Earth, Jupiter, and Saturn, and discuss how these limitations affect our ability to model the complete coupled system.