Uranus is the seventh planet from the Sun and an ice giant. Its blue-green color comes largely from methane in the upper atmosphere, which absorbs red light. The planet has a deep atmosphere, an unusual magnetic field, faint rings and moons; it does not have a solid surface like Earth.
At a glance
Orbit: About 84 Earth years. Axial tilt: About 98 degrees. Type: Ice giant. Only spacecraft flyby: NASA’s Voyager 2 in 1986. Its equator is almost at a right angle to its orbital path, so Uranus appears to rotate on its side.
An extreme set of seasons
The sideways tilt makes the Sun illuminate Uranus’s poles in an unusual way over its long orbit. Near a solstice, a pole can spend years facing the Sun while the other remains dark. Scientists study the changing clouds and temperature to understand how the atmosphere responds to that sunlight. A day is much shorter than a year, lasting roughly 17 hours.
Rings, moons and interior
Uranus has dark, narrow rings that are less conspicuous than Saturn’s. Its moons include Miranda, Ariel, Umbriel, Titania and Oberon; Miranda is especially notable for varied terrain seen by Voyager 2. “Ice giant” describes a different mix of materials from Jupiter and Saturn: water, ammonia and methane are important to models of the interior, though conditions at depth are far removed from familiar ice.
What spacecraft and telescopes reveal
Voyager 2 provided our only close spacecraft look in 1986, measuring the planet, magnetic environment, rings and moons. Hubble and the James Webb Space Telescope have since shown changing atmospheric features and clearer views of its faint ring system. A future orbiter and probe could answer questions about the interior, atmosphere and moons; no such mission has yet made a second close visit.
Explore NASA images and sources
NASA Uranus image gallery · NASA Uranus Photojournal gallery · NASA Uranus facts. Check image credits and usage terms on each image page.
Return to the Solar System guide.
