Shadows on the "B"-Ring (Natural Colors; credits: Lunar Explorer Italia)

Caption NASA:"The shadow of the moon Epimetheus stretches across the B-Ring in this image taken by Cassini as Saturn approaches its 2009 Equinox. 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.
This view looks toward the sunlit side of the rings from about 42° below the Ring-Plane.

The image was taken in Visible Light with the Cassini Spacecraft narrow-angle camera on June 8, 2009. The view was obtained at a distance of approx. 700.000 Km (about 435.000 miles) from Saturn and at a Sun-Saturn-Spacecraft, or Phase, Angle of 129°.
Image scale is roughly 4 Km (about 2,5 miles) per pixel".