Uranus spins on its side at a 98-degree angle.

Researchers at Durham University used computer simulations in 2018 to study why Uranus tilts. They believe an object twice the size of Earth hit the planet about 4 billion years ago. This collision was likely a glancing blow that knocked the planet over but did not destroy its atmosphere.Uranus takes 84 Earth years to orbit the Sun once. Because of its tilt, the Sun shines directly on one pole during the summer. This creates strange weather with winds reaching 560 miles per hour. The planet has 27 moons and a ring system that also orbit at this tilted angle.Scientists think these moons formed from the debris left over after the giant collision. Uranus is known as an ice giant because it is made of water, methane, and ammonia. It has the coldest atmosphere in the solar system at -224 degrees Celsius. The Voyager 2 spacecraft confirmed these details when it flew past the planet in 1986.