The Rings

Caption NASA:"The contrast is sharp between the outer portion of the A-Ring edge and the Ring's main body. One explanation for this is that the outer A-Ring region contains smaller particles (around 1 cm or 0,4" in radius) than the main rings, allowing more opportunities for light scattering before it scatters toward the camera.
Ringlets in the Encke Gap and flanking the bright F-Ring core are clearly visible here.

This view looks toward the lit side of the Rings from about 4° below the Ring-Plane.

The image was taken with the Cassini spacecraft narrow-angle camera using a spectral filter sensitive to wavelengths of infrared light centered at 752 nanometers on Nov. 7, 2006. Cassini was then at a distance of approx. 1,1 MKM (about 700.000 miles) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 140°.
Image scale on the sky at the distance of Saturn is about 6 Km (a little less than 4 miles) per pixel".