Uranus is the seventh planet from the Sun and has the third-largest diameter in our solar system. It was the first planet found with the aid of a telescope. This planet has an atmosphere made mostly of molecular hydrogen and atomic helium, with a small amount of methane. Also, Uranus is an ice giant. Most of its mass is a hot, dense fluid of icy materials – water, methane, and ammonia – above a small rocky core. That's why it has such a bright color in our Uranus Planet Gradient cursor pack.