Saturn’s Rings and Moons

Description

The gas giant planet Saturn has an extensive ring system that extends outwards for tens of thousands of kilometres. Here, both Saturn and the Sun (neither seen) are to the left, with the planet’s shadow cast across its rings. Two moons are seen as crescents: Mimas in the foreground (396 kilometres across) and Epimetheus (113 kilometres across) in the background. Both orbit on the outer edge of the main ring system, helping to clear and maintain the gaps in the rings. This mosaic of images was obtained on 24 October 2009, by the narrow-angle camera on the orbiting Cassini spacecraft. (Photo by Science Photo Library)