Tilt of Uranus

Uranus has the most extreme axial tilt in the solar system—a staggering 98 degrees—making it essentially rotate on its side. Unlike other planets, which spin like tops, Uranus rolls like a ball, with its poles facing the Sun during solstices. Scientists believe this extreme tilt was caused by a colossal collision with an Earth-sized object early in its formation. This unique orientation leads to extreme seasonal variations, with each pole experiencing 42 years of continuous sunlight followed by 42 years of darkness.