While Neptune and Uranus are similar in many ways, new observations have revealed why Uranus might be the paler of the two. The new research suggests the reason for the difference in color lies in a haze that exists on both planets and is thicker on Uranus.

Neptune and Uranus are similar in mass, size, and atmospheric compositions. However,

Source: Hot Hardware – Why Astronomers Are Sniffing Around The Methane Gas Of Uranus