Giant Planet Aurorae

Presented by Licia Ray, University of Colorado

While we are most familiar with the Earth's aurora, the giant planets of the solar system exhibit similar phenomena. Jupiter has three distinct auroral regions: the Io spot and tail, main oval, and variable polar aurora. At Jupiter, the main aurora is caused by an internally driven, steady-state process and is directly connected with the transfer of angular momentum from Jupiter to radially transported Io-genic plasma. Recent work has shown that field-aligned potentials are crucial to this process at Jupiter. Saturn also exhibits bright aurora, although it is unclear whether or not there are distinct satellite-related emissions as at Jupiter and to what extent Enceladus (Saturn's second major satellite) drives these emissions.