Exploring the Planets

Uranus Facts

Discoverer: Sir William Herschel (1781)
Spacecraft Encounter(s): Voyager 2 (1986)
Mean distance from the Sun: 19.19 AU
(2.871 billion km/1.784 billion mi)
Length of Year: 84.01 Earth years
Rotation Period: 17.24 hours
Mean Orbital Velocity: 6.81 km/s (4.2 m/s)
Inclination of Axis: 97.92°
Diameter: 51,118 km (31,765 mi)
Number of observed satellites: more than 20


Comparisons With Earth:
Diameter: 4.0 x Earth's
Average Distance from the Sun: 19.2 x Earth's
Mass: 14.5 x Earth's
Density: 0.22 x Earth's

Uranus, towards the planet's pole of rotation

These two pictures of Uranus were compiled from images recorded by Voyager 2 on January 10, 1986, when the NASA spacecraft was 18 million kilometers (11 million miles) from the planet.