Both Jupiter and Saturn have magnetic fields much stronger than Earth’s (Uranus, Neptune and Mercury are also magnetic), and both have large radiation belts. Aurora has been observed on both, most clearly with the Hubble Space Telescope.
These auroras seem, like Earth’s, to be powered by the solar wind. In addition, however, Jupiter’s moons, especially Io, are also powerful sources of auroras. These arise from electric currents along field lines (“field aligned currents”), generated by a dynamo mechanism due to relative motion between the rotating planet and the moving moon. Io, which has active volcanism and an ionosphere, is a particularly strong source, and its currents also generate radio emissions, studied since 1955. – wiki
Credit: All images are provided by NASA and the ESA