Saturn's rings, as seen by the wide angled camera on NASA's Cassini spacecraft. This view looks toward the unlit side of the rings from about 23 degrees above the rings' plane, with the planet casting its shadow across them. A sliver of light (bottom left) is seen through the rings. Saturn's rings are mainly composed of ice and dust particles. Image taken on 11th September 2006, from a distance of around 1.1 million kilometres away