Uranus rolls around the Sun on its side. Its axis is tipped over by 98 degrees, probably after something huge smashed into it long ago.
That makes its seasons extreme. Each pole gets about 42 years of daylight, followed by 42 years of darkness.
It has the coldest air of any planet, dropping to about −224 °C, even colder than Neptune further out.
It was the first planet found with a telescope, by William Herschel in 1781. Before that, nobody knew the solar system had a seventh world.
Only one spacecraft has ever visited: Voyager 2, flying past in 1986. Most of its 29 moons are named after characters from Shakespeare.
- Width
- 50,724 km
- One day
- 17.2 hours, spinning backwards
- One year
- 84.0 Earth years
- Moons
- 29
- Temperature
- −195 °C at the cloud tops
- 70 kg on Earth weighs
- 63 kg here
