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.
You might also be interested in:
If someone says they saw an aurora, you might picture something like this. There is another type of aurora that we can't see. These aurora are called SAR arcs. The SAR stands for Stable Auroral Red. That...more
Uranus' plasmasphere is tiny. The rings of Uranus sweep away much of the particles in the area. Particles enter the plasmasphere from the atmosphere as well as the magnetotail. Mathematical theory suggests...more
This picture shows the flowing of particles into and out of the auroral zone, as Field-Aligned currents (FAC's) take at short-cut through the atmosphere. Some of the particles entering the auroral zone...more
There is not very much radio noise within the magnetosphere of Uranus. Signals are observed with much less power than observed at Saturn, but several times greater than observed at Earth. The signals...more
The magnetosphere of Uranus is medium sized, but still much bigger than the Earth's. It holds all of Uranus' moons. It is probably made in the middle of the planet, and with ice, rather than with iron...more
Uranus has a strange magnetic field. The magnetic poles of Uranus are not at all close to the geographic poles of Uranus. The main magnetic field of Uranus is tilted 59° away from the planet's spin axis....more
Besides methane, Uranus' atmosphere contains even more complex molecules. These molecules form layers of smog over the clouds of Uranus, as shown in the picture. ...more