From the inside out, the "Cassini division" in faint red at left is followed by the A ring in its entirety in this ultraviolet-light image. The A ring begins with a "dirty" interior of red followed by more blue as it spreads away from the planet. The blue is a signature of water ice. The red band roughly three-fourths of the way outward in the A ring is known as the Encke gap. Credit: NASA/JPL
