This Cassini image captures three of Saturn's ring moons in a single view. From left to right, the moons seen in this view are Pandora (81 kilometers, 50 miles across), Janus (179 kilometers, 111 miles across) and Prometheus (86 kilometers, 53 miles across).
The ring moons are an interesting study in the dynamics of orbiting bodies. Prometheus and Pandora shepherd the thin F ring, whose particles orbit between the pair. Prometheus has been observed 'stealing' material from the F ring in images from Cassini. The orbit of Janus is within 50 km of the orbit of another moon, slightly smaller Epimetheus, and the two exchange positions in their orbital path (inner to outer) every four years.
Saturn's bright, icy rings are overexposed in the scene. However, this has helped make visible material present within the Cassini Division (near lower right).
This view is from Cassini's vantage point beneath the ringplane. The image was taken in visible light with the narrow angle camera on January 29, 2005, from a distance of approximately 3.4 million kilometers (2.1 million miles) from Saturn. The image scale is 20 kilometers (12 miles) per pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini-Huygens mission for NASA's Science Mission Directorate, Washington, D.C. The imaging team consists of scientists from the US, England, France, and Germany. The imaging operations center and team lead (Dr. C. Porco) are based at the Space Science Institute in Boulder, Colo.