Shop Windows to the Universe

The Universe at Your Fingertips 2.0 DVD from the Astronomical Society of the Pacific is in our online store, filled with Earth and space science resources.

Click on image for full size
Images courtesy of Wikipedia [magnetic field diagram] and NASA, ESA, L. Sromovsky and P. Fry (University of Wisconsin), H. Hammel (Space Science Institute), and K. Rages (SETI Institute) [Uranus photo].

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. Earth's magnetic field is tilted, too... but only by 11. The magnetic field of Uranus is shifted, too. It doesn't quite go through the center of the planet.

The magnetic field of Earth is pretty much like the magnetic field around a bar magnet. It has a North Pole and a South Pole. It is called a dipole ("two poles") field. The magnetic field of Uranus is more complicated. It has a dipole part... but it also has a part with four poles. With all of these poles and its crazy tilt, the magnetic field on Uranus varies a lot from place to place. In some places in the southern hemisphere of Uranus the magnetic field is only 1/3rd as strong as Earth's field. However, in some parts of the North the field on Uranus is almost four times as strong as Earth's!

Why is the Uranian magnetic field so odd? Scientists think that electrical currents in a salty ocean inside Uranus may create its magnetic field. That ocean isn't at the core of Uranus. Most planets make their magnetic field at their core. Maybe that's why the field around Uranus is so odd. Neptune is the other planet most like Uranus. Neptune has a strange magnetic field, too.

The spin axis of Uranus is tilted 98 and the magnetic field is tilted 59. Scientists thought that these tilts would give Uranus a very strange magnetosphere. Guess what? The magnetosphere of Uranus is pretty much normal, like other planets. Scientists are still trying to figure out why. They do know that Uranus has aurora... like the Southern and Northern Lights on Earth.

Last modified May 5, 2009 by Randy Russell.

Shop Windows to the Universe Science Store!

Our online store includes fun classroom activities for you and your students. Issues of NESTA's quarterly journal, The Earth Scientist are also full of classroom activities on different topics in Earth and space science!

Windows to the Universe Community

News

Opportunities

You might also be interested in:

The Poles of Uranus

Uranus is the tilted planet. The axis through its North and South Poles is tilted by 98. In other words, Uranus is lying on its side! That's not all - the magnetic field of Uranus is tilted, too. The...more

Dipole, Quadrupole, and Multipole Magnetic Fields

Have you ever seen a bar magnet? Bar magnets have two magnetic poles - north and south. The magnetic field around a bar magnet is called a dipole magnetic field. "Dipole" means "two poles". Bar magnets...more

The Making of Uranus' Magnetosphere

Magnetospheres are generated with 1.) magnetic materials and 2.) with motions within the magnetic material. The Earth-like planets generate magnetospheres within the iron cores at the center. However,...more

Generating a Magnetic Field

Scientists think, although not certain, there are two essential ingredients for generating a magnetic field. Those two ingredients are magnetic material currents A bar of iron can be made into a magnet...more

Motions in Uranus' Interior

Motions in the interior of a planet help carry heat from the inside to the outside. The drawing to the left illustrates the kind of movements that happen in interior of a planet. Material rises from the...more

An Overview of Uranus' Atmosphere

The plain aquamarine face of Uranus confirms the fact that Uranus is covered with clouds. The sameness of the planet's appearance shows that the planet's atmosphere is mostly composed of one thing, methane....more

Uranus' Moons and Rings

Uranus has // Call the moon count function defined in the document head print_moon_count('uranus'); fascinating moons and a complicated ring system. The ring is a completely different form of ring than...more

An Overview of Uranus' Interior

The Giant planets do not have the same layered structure that the earthlike planets do. Their evolution was quite different than that of the earthlike planets, and they have much more gas and ice inside....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