Prometheus' Trail

Caption NASA:"Seen here is the end result of the process that occurs every time the moon Prometheus closely approaches Saturn's F-Ring. The moon cuts a dark channel in the ring's inner edge that then shears out over successive orbits, giving the inner edge of the ring the grooved appearance seen here.
This process is described in detail, along with a movie of Prometheus creating one of the streamer/channel features, in Soft Collision.
The view is toward the sunlit side of the Rings from about 3° below the Ring-Plane.

The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Oct. 25, 2007. The view was acquired at a distance of approx. 624.000 Km (such as about 388000 miles) from Saturn and at a Sun-Ring-Spacecraft, or phase, angle of 23°.
Image scale is roughly 3 Km (about 2 miles) per pixel".