File:Saturn system transits.jpg

English: Four Saturn moons as seen from Cassini. Dione transits Titan by the en:rings of Saturn. Prometheus transits the rings.

In a rare moment, the Cassini spacecraft captured this enduring portrait of a near-alignment of four of Saturn's restless moons. Timing is critical when trying to capture a view of multiple bodies, like this one. All four of the moons seen here were on the far side of the rings from the spacecraft when this image was taken; and about an hour later, all four had disappeared behind Saturn.

Seen here are Titan (5,150 kilometers, or 3,200 miles across) and Dione (1,126 kilometers, or 700 miles across) at bottom; Prometheus (102 kilometers, or 63 miles across) hugs the rings at center; Telesto (24 kilometers, or 15 miles across) is a mere speck in the darkness above center.

The image was taken in visible light with the Cassini narrow-angle camera on Oct. 17, 2005 at a distance of approximately 3.4 million kilometers (2.1 million miles) from Dione and 2.5 million kilometers (1.6 million miles) from Titan. The image scale is 16 kilometers (10 miles) per pixel on Dione and 21 kilometers (13 miles) per pixel on Titan.