Event Details

Friday Seminar - Speaker: Siyuan Wu University of Southampton, UK

Abstract

Saturn’s narrowband emissions were first discovered during the Voyager flyby in the 1980s. These emissions are believed to be analogous to the continuum radiation observed at Earth and Jupiter, generated through mode conversion processes. Typically observed at frequencies below 100 kHz for Earth and Jupiter, Saturn’s narrowband emissions are most prominent in the 5 kHz and 20 kHz bands. Case studies suggest that these emissions result from mode conversion of upper hybrid waves or Z mode waves, both of which are amplified by plasma instabilities. The emissions themselves exhibit intriguing features such as high-latitude propagation, trapping, depolarization, and harmonics. Recent research has linked these narrowband emissions to plasma injection events at Saturn, which are thought to be driven by magnetic reconnection or interchange instabilities, highlighting their potential role as diagnostic tools for understanding Saturn’s magnetospheric dynamics. Additionally, these emissions exhibit rotational modulation linked to the distinct periods of Saturn’s northern and southern magnetospheres, mirroring patterns seen in other magnetospheric data and suggesting an influence from larger-scale magnetospheric convection processes. This talk will provide an overview of Saturn’s narrowband emissions and discuss recent advancements in the understanding of their origins and characteristics.