Jupiter is the most massive planet in the solar system, and given that knowledge, it's not too absurd to think that Jupiter has some of the most significant auroras. In fact, Jupiter's auroras are so large that the entire planet Earth could fit inside of one.
Despite what you've heard about Jupiter's auroras, they're anything but just like Earth's. That's just a lazy scientist's way of saying, "yeah the Earth has auroras too." Truthfully, no one knows what causes Jupiter's intense auroras. In fact, many of NASA's current theories are presumably mistaken.
NASA is trying to solve the mysteries behind Jupiter's auroras with the help of the Juno probe, which gets close to Jupiter every so often during orbit to take measurements of the planet. Using the onboard Jupiter Energetic Particle Detector Instrument (JEDI), Juno can develop a metric for understanding Jupiter's magnetic fields.
Although we understand how powerful Jupiter's auroras are, we still have trouble determining where exactly they originate. What we do know is that they aren't formed the same way as Earth's auroras are and that the planet's own internal mechanisms may influence how the auroras behave and why they're as powerful as they are.
One can only hope that future Jupiter-probing missions will help us come up with the answers to our ongoing questions about why Jupiter is so mysterious.