Mean distance from Sun: 2,870,972,200 km
Orbital Period: 84.0205 years
Rotational Period: 17 hours, 14 minutes
Composition: hydrogen, helium, methane
All the Jovian planets (gas giants) in our solar system are comprised primarily of the same elements as our Sun. They are all considered failed stars because they are not massive enough to initiate and sustain nuclear fusion, the energy process that powers the Sun and all other stars. The aurorae observed on the planet last for only a few minutes at a time, just as they do on Earth. However, unlike on Earth, the aurorae occur far from the poles. This is because Uranus’ magnetic field is tilted 59 degrees in respect to its rotation axis, compared to 11 degrees for Earth. Also, the axis of the magnetic field does not pass through the planet’s core. Scientists theorize that Uranus’ magnetic field is generated by a salty ocean within the planet, resulting in the off-center magnetic axis.
Uranus, as with the other Jovian planets, is a giant sphere of electrically active plasma. Its magnetic poles act as a cathode and anode in an electrical discharge of the ionized particles that comprise the planet. The planet’s magnetic field is inclined at such a steep angle because it remains roughly perpendicular to the orbital plane of the solar system, like all other planetary magnetic fields, even though Uranus’ spin axis is almost level with the orbital plane. It should be noted that the magnetic poles of Uranus are reversed, pointing south to north in relation to the orbital plane, same as Earth.