The Hubble team states that:
“The variability of the auroras is influenced by both the solar wind and the rapid rotation of Saturn, which lasts only about 11 hours. The northern aurora displays two distinct peaks in brightness -at dawn and just before midnight. The latter peak, unreported before, seems specific to the interaction of the solar wind with the magnetosphere at Saturn’s solstice.”
Other planets have auroras too such as Jupiter, Saturn, Uranus and Neptune, also some exoplanets show some evidence of auroral activity. However, auroras are unique to each planet for instance Jupiter’s permanent aurora is not caused by solar wind but some mysterious mechanism yet to be discovered.
And while Saturn’s main auroral ring seems to be solar wind-generated, there are patches of it that are not, which is still a mystery.