Uranus, GOD OF THE SKY: Uranus is the third largest planet in our Solar System. Uranus has nine major rings and 27 known moons. This image, taken in infrared light, reveals cloud structures not normally visible to human eyes. Methane gas in the upper atmosphere absorbs red light, giving the planet its blue-green color. Uranus is spinning on its side, probably because of a collision with a large object early in the Solar System's history.