Saturn from Titan, Illustration of the planet Saturn and its rings and some of its moons, viewed from the upper part of the atmosphere of its largest moon Titan. Titan has a thick atmosphere of nitrogen and organic compounds, mainly methane and ethane. This gives the moon its characteristic orange colour. Titan's atmosphere extends around 880 kilometres above its surface. Saturn is the second largest of the planets in the solar system, having a diameter in excess of 120,000 kilometres.