Ultraviolet and infrared observations of Saturn's auroral oval

Abstract

New observations of Saturn's southern auroral oval made simultaneously in ultraviolet (UV) and infrared (IR) wavelengths show how complex and dynamic the auroral oval is. Melin et al. present high‐spatial‐resolution observations from the Cassini spacecraft's UV and IR instruments. The auroral oval varies over short time scales and has many small‐scale structures. The researchers observed three different arcs within the auroral oval, which they suggest are probably caused by precipitation of particles with different energies. In addition, the researchers found that the main auroral oval is morphologically similar in UV and IR, but in the auroral emissions equatorward and poleward of the main oval, there are noticeable differences in UV and IR, highlighting the need for observations at a range of wavelengths. (Geophysical Research Letters, doi:10.1029/2011GL048457, 2011)