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Uranus is the seventh planet from the Sun, and the third largest planet in our solar system. It appears to spin sideways.

Uranus is the seventh planet from the Sun, and the third largest planet in our solar system – about four times wider than Earth.

Uranus is very cold and windy. It is surrounded by faint rings, and more than two dozen small moons. It rotates at a nearly 90-degree angle from the plane of its orbit. This unique tilt makes Uranus appear to spin on its side.

Only one spacecraft has explored planet Uranus.

Resources for Uranus and Neptune.

Explore a curated collection of resources about ice giants, including activities that can be done at home, as well as videos and animations, images, and posters.

Only one spacecraft has visited distant Uranus. After traveling more than 1.8 billion miles (3 billion kilometers) in nine years, NASA's Voyager 2 gathered much of its critical information about the mysterious planet, including its rings and moons, in just six hours. The rest of what we know about Uranus comes from observations via the Hubble Space Telescope and several powerful ground-based telescopes.

The first human-made object to fly past Uranus, Voyager 2 discovered 10 new moons, two new rings, and a magnetic field stronger than Saturn's, while returning images and data that still fuel discoveries today.

Uranus is the seventh planet from the Sun, and it has the third largest diameter of planets in our solar system. Uranus appears to spin sideways.

Uranus is a very cold and windy world. The ice giant is surrounded by 13 faint rings and 28 small moons. Uranus rotates at a nearly 90-degree angle from the plane of its orbit. This unique tilt makes Uranus appear to spin sideways, orbiting the Sun like a rolling ball.

Uranus was the first planet found with the aid of a telescope. It was discovered in 1781 by astronomer William Herschel, although he originally thought it was either a comet or a star. It was two years later that the object was universally accepted as a new planet, in part because of observations by astronomer Johann Elert Bode.

William Herschel tried unsuccessfully to name his discovery Georgium Sidus after King George III. Instead, the planet was named for Uranus, the Greek god of the sky, as suggested by Johann Bode.

Uranus' environment is not conducive to life as we know it. The temperatures, pressures, and materials that characterize this planet are most likely too extreme and volatile for organisms to adapt to.

With an equatorial diameter of 31,763 miles (51,118 kilometers), Uranus is four times wider than Earth. If Earth was the size of a nickel, Uranus would be about as big as a softball.

The moons are sometimes called the "literary moons" because they are named for Shakespearean characters, along with a couple of the moons being named for characters from the works of Alexander Pope.