The broad shadow across the giant planet is cast by Saturn's dense B ring with intriguing threadlike shadows from Saturn's inner C ring arrayed below.
While the B and C rings are otherwise not visible here, the very narrow outer F ring lies toward the bottom of the image as well as a section of the partly transparent A ring and its 300 kilometer wide Encke gap crisscrossing the ring shadows.
Sunlight streaming through the much larger Cassini gap that separates the A and B rings is responsible for the bright band seen above Mimas.
The Cassini gap itself is just off the bottom of this cropped view.
Orbiting well beyond Saturn's F ring, Mimas is a mere 400 kilometers in diameter.