Spokes!

Caption NASA originale:"A broad and ghostly spoke drifts past under the Cassini spacecraft's gaze. The spoke-forming region of the B-Ring displays faint longitudinal variations in brightness, from left to right, a feature seen also in other images.
This view looks toward the unlit side of the Rings from about 35° above the Ring-Plane.

The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Oct. 17, 2006 at a distance of approx. 2 MKM (such as about 1,3 MMs) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 158°. Image scale is roughly 12 Km (about 7 miles) per pixel".