-224 degrees

The average temperature of Uranus is estimated to be about -224 degrees Celsius. This is among the lowest average temperatures of any planet in the solar system.

13 pieces

The rings of Uranus were discovered relatively late because they are dark and faint, and 13 have been confirmed so far. These rings are characterized by their extreme darkness, and the main rings are named Epsilon, Beta, Gamma, and so on. The most notable Epsilon ring is the outermost of Uranus’s rings.

blue

Uranus’s atmosphere is rich in methane gas, and because methane absorbs the red wavelengths of sunlight, the planet appears blue to blue-green. For this reason, when observed through a telescope from Earth, it characteristically looks blue.

Uranus

The English name of 天王星 is “Uranus.” It was named after Uranus, the sky god in Greek mythology. In the solar system, Uranus is the only planet whose name comes from Greek mythology; the other planets use Anglicized names of Roman deities.

about 84 years

Uranus takes about 84 Earth years to complete one orbit around the Sun. Since its discovery in 1781, Uranus has not yet completed a single full orbit around the Sun. Its great distance from the Sun and its slow orbital speed result in this long orbital period.

Ice of water, methane, and ammonia

Uranus consists mainly of ices—water, methane, and ammonia—along with an atmosphere of hydrogen and helium. Rock and metal are thought to exist in its central core, but because most of the planet is made of “ice,” it is classified as an ice giant.

about 2.8 billion km

The average distance from Earth to Uranus is about 2.8 billion kilometers. Uranus’s orbit is elliptical, so its distance from the Sun varies between perihelion (closest) and aphelion (farthest), but taking the average gives roughly 2.8 billion km.