The Great Crossing of Saturn's rings

This spectacular movie sequence of Saturn and its ring system was obtained thanks to clear-filter images taken with the Cassini spacecraft wide-angle camera on 17 January 2007, at a distance of approximately 900 000 kilometres from Saturn. The image scale is 48 kilometres per pixel. This movie begins with a view looking toward the lit side of the rings from about 9° below the ring plane and ends when the spacecraft is 8° above the ring plane.

The movie captures Saturn's rings during a ring plane crossing - which Cassini makes twice per orbit - from the spacecraft's point of view. The movie begins with a view of the sunlit side of the rings. As the spacecraft speeds from south to north, the rings appear to tilt downward and collapse to a thin plane, and then open again to reveal the un-illuminated side of the ring plane, where sunlight filters through only dimly.
The striking contrast between the sunlit and unlit sides of the ring plane can now be fully appreciated, thanks to the sense of continuity in time and space provided by this brief clip.

The movie consists of 34 images taken over the course of 12 hours as Cassini pierced the ring plane. Additional frames were inserted between the original images in order to smooth the motion in the sequence (a scheme called ‘interpolation’).

Six moons careen through the field of view during the sequence. The first large one is Enceladus, whose slanted motion from the upper left to centre right nicely illustrates the inclination of its orbit with respect to the rings. The second large one, seen in the second half of the movie, is Mimas, going from right to left.