This is an image of the type-B aurora of Earth, also called the SAR ARC.
L. Frank from Dynamics Explorer

Uranus Aurora

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.


Last modified May 7, 2009 by Randy Russell.

You might also be interested in:

Cool It! Game

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

The SAR Arc

The aurora we are most familiar with is the polar aurora. This is what people are talking about when they say the northern or southern lights. But there are other less-known aurora, such as SAR arcs....more

Uranus' Plasmasphere

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

The forming Aurora

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

The Radio Signals of Uranus

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

A Look at Uranus' Magnetosphere

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

The Magnetic Poles of Uranus

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

Uranus' Smog

Besides methane, Uranus' atmosphere contains even more complex molecules such as ethane gas. (These gases are similar to the exhaust gases that come out of cars on earth). These molecules form layers of...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA