One of Cassini’s greatest discoveries are the ice geysers pouring out of Saturn’s moon Enceladus. Recent research by the NASA/ESA Cassini team suggests that this icy moon isn’t the only geologically-active world orbiting the ringed planet. Two other Saturnian moons, Tethys and Dione, are shooting streams of charged particles into space, and this may be a sign of geysers like those on Enceladus.

https://www.esa.int/Science_Exploration/Space_Science/Cassini-Huygens/Two_more_active_moons_around_Saturn