Prometheus, its Shadow and Streamer Channel

Caption NASA:"The moon Prometheus casts a shadow on the thin "F"-ing marked with Streamer-Channels created by the moon in this image taken as Saturn approaches its August 2009 Equinox.
The gravity of potato-shaped Prometheus (about 86 Km, or approx. 53 miles across) periodically creates Streamer-Channels in the "F"-Ring.

(For further examples and to learn more, see PIA10461 and PIA10593. If you want to watch a movie of this process, please refer to and see PIA08397).

The novel illumination geometry created as Saturn approaches its August 2009 Equinox allows moons orbiting in or near the plane of Saturn's Equatorial Rings to cast shadows onto the Rings. These scenes are possible only during the few months before and after Saturn's Equinox which occurs only once in about 15 Earth years.
To learn more about this special time and to see movies of moons' shadows moving across the Rings, see PIA11651 and PIA11660.

This view looks toward the unilluminated side of the Rings from about 52° above the Ring-Plane. The image was taken in Visible Light with the Cassini Spacecraft narrow-angle camera on June 15, 2009.
The view was acquired at a distance of approx. 1,8 MKM (about 1,1 MMs) from Prometheus and at a Phase Angle of 85°.
Image scale is roughly 11 Km (a little less than 7 miles) per pixel".