Space Weather at Saturn - Auroral observations

Unlike to Earth, Saturn is a fast rotator and its magnetosphere is dominated by fast planetary rotation and internally driven processes. However, the interaction of the solar wind with Saturn’s magnetosphere is not negligible and it is manifested among others in the auroral region. The interplanetary magnetic field reconnects with the dayside magnetopause at Saturn and results in enhancements in the auroral emission accompanied by entry of significant amount of open flux in the magnetosphere. The solar wind affects also the nightside magnetosphere. Dramatic enhancements of the nightside-dawn auroral emissions have been attributed to solar wind-induced auroral storms. Additionally, recent auroral observations revealed the presence of a transpolar arc at Saturn, one of the most spectacular auroral features at Earth, which could be possibly related to solar wind driven tail reconnection. Finally, there is evidence of viscous interaction of the solar wind with Saturn’s magnetosphere, which involves magnetic reconnection on a small scale.