Saturn's ring system starts about 7,000 kilometers above its clouds. Despite extending for about 270,000 kilometers, it is only about 200 meters thick, hence the knife-edge appearance when viewed side-on. Although they look like solid discs, the rings are in fact made of water-ice particles, which range in size from tiny specks of dust to boulders measuring 10 meters in diameter. The Vogager 2 spacecraft captured this image, which has been colour-enhanced. In reality the rings are reddish brown, cream and tan due to impurities in the ice, such as iron oxide (rust), and to ice crystal damage from the Sun's ultraviolet radiation.