Overview of Saturn lightning observations

TL;DR

This paper reviews six years of Saturn lightning observations using Cassini's instruments and ground-based support, highlighting the detection methods, chemical implications, and comparisons with Jupiter and Earth lightning.

Contribution

It provides a comprehensive summary of Saturn lightning observations from multiple instruments and compares them with lightning phenomena on other planets.

Findings

Detection of Saturn's lightning via radio and optical methods

Chemical signatures possibly linked to lightning activity

Comparison of Saturn lightning characteristics with Jupiter and Earth

Abstract

The lightning activity in Saturn's atmosphere has been monitored by Cassini for more than six years. The continuous observations of the radio signatures called SEDs (Saturn Electrostatic Discharges) combine favorably with imaging observations of related cloud features as well as direct observations of flash-illuminated cloud tops. The Cassini RPWS (Radio and Plasma Wave Science) instrument and ISS (Imaging Science Subsystem) in orbit around Saturn also received ground-based support: The intense SED radio waves were also detected by the giant UTR-2 radio telescope, and committed amateurs observed SED-related white spots with their backyard optical telescopes. Furthermore, the Cassini VIMS (Visual and Infrared Mapping Spectrometer) and CIRS (Composite Infrared Spectrometer) instruments have provided some information on chemical constituents possibly created by the lightning discharges and transported upward to Saturn's upper atmosphere by vertical convection. In this paper we summarize the main results on Saturn lightning provided by this multi-instrumental approach and compare Saturn lightning to lightning on Jupiter and Earth.