This is an image of the type-B aurora of Earth, also called the SAR ARC.
L. Frank from Dynamics Explorer
Even though aurora have been seen in the atmosphere of Uranus (which is centered around the magnetic pole as it should be for type-A aurora) Uranus mostly has type-B aurora similar to the auroras of Earth (shown here).
The rings of Uranus sweep away much of the particles in the area which is supposed to be the plasmasphere. Therefore there is only a small plasmasphere containing trapped particles, and a lot less plasma can be forced from the magnetosphere down into the atmosphere to create the aurora.
The type-A aurora probably comes from current systems which connect the moon Miranda to the magnetic pole of Uranus, however radio signals, which are thought to be made when the aurora is being created, are very weak at Uranus. This makes rebuilding the processes which create the aurora difficult.
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