Cassini / UVIS

Saturn's Spinning Northern Lights

 

UVIS obtained 26 images of Saturn's auroras on May 25, 2007 over an 8 hour 15 minute period, most of a planetary rotation period. They are presented here as side-by-side animations of simultaneous observations from two UVIS channels, the Extreme Ultraviolet (EUV) and the Far Ultraviolet (FUV). They show Saturn's northern auroral lights, created by electrons from Saturn's magnetosphere striking hydrogen gas in the atmosphere. The EUV channel (left) shows primarily the auroral emissions. The FUV channel (right) also shows sunlight scattered by atmospheric gas creating a "bright limb" on the sunlit left side. The auroral lights mostly take the form of an oval, although variable spots of emission are seen inside the oval. The animations show auroral brightness features rotating as the planet and its magnetosphere rotate. The auroral arc splits into two arcs on the night side. One of Saturn’s moons appears briefly at the upper left near the end of the FUV channel movie. These images were processed by UVIS Co-Investigator Wayne Pryor, a Professor at Central Arizona College.


LASP