The shadow of the moon Mimas strikes the F ring at a different angle than the angle at which it is cast on the A ring, illustrating differences in the vertical heights of the rings in this image taken as Saturn approaches its August 2009 equinox.
Gray Mimas appears to hover above the colorful rings. The large crater seen on the right side of the moon is named for William Herschel, who discovered Mimas in 1789.
This mosaic, created from images taken by NASA's Cassini spacecraft, looks straight at Saturn's moon Mimas' huge Herschel Crater revealing bright-walled craters, with floors and surroundings about 20 percent darker than the steep crater walls.
Saturn's rings lie between a pair of moons in this view from NASA's Cassini spacecraft that features Mimas and Prometheus. Mimas is the more noticeable of the two moons at top left, Prometheus is near the center of image and closest to Cassini.
While cruising around Saturn in early October 2004, Cassini captured a series of images that have been composed into the largest, most detailed, global natural color view of Saturn and its rings ever made.
NASA's Cassini Orbiter captured this natural color view of Saturn almost a month after the planet's August 2009 equinox. The shadow cast on the planet by the rings remains narrow.
Saturn storms observed by NASA's Voyager, Aug. 5, 2004. Voyager 1 and 2 observed radio signals from lightning which were interpreted as being from a persistent, low-latitude storm system.
In this view captured by NASA's Cassini spacecraft on its closest-ever flyby of Saturn's moon Mimas, large Herschel Crater dominates Mimas, making the moon look like the Death Star in the movie 'Star Wars.'
Although Mimas holds the unofficial designation of 'Death Star moon,' Tethys is seen here also vaguely resembling the space station from Star Wars. Apparently, Tethys doesn't want Mimas to have all the fun!
Saturn's moon Mimas appears near Saturn, dwarfed by its parent planet in this image. Mimas appears tiny compared to the storms clearly visible in far northern and southern hemispheres of Saturn.
A quintet of Saturn's moons come together in this portrait from NASA's Cassini spacecraft. Janus is seen on the far left, Pandora orbits near the middle, Enceladus appears above the center, and Rhea and Mimas are seen on the right side.
The small moon Mimas passes in front of the larger moon Rhea which is partly obscured by Saturn's rings in this image from NASA's Cassini spacecraft. Go to the Photojournal to view the animation.
Saturn and its north polar hexagon dwarf Mimas as the moon peeks over the planet's limb. Saturn's A ring also makes an appearance on the far right. Mimas is 246 miles (396 kilometers) across.
Janus is spotted over Saturn's north pole in this image while Mimas' shadow glides across Saturn in this image from NASA's Cassini spacecraft. Janus is the faint dot that appears just above Saturn's north pole.
Saturn's moon Mimas peeks out from behind the night side of the larger moon Dione in this image captured by NASA's Cassini spacecraft during the Dione flyby of Dec. 12, 2011.
The largest storm to ravage Saturn in decades started as a small spot seen in this image from NASA's Cassini spacecraft on Dec. 5, 2010 -- the same day Cassini also detected frequent lightning signals.
Saturn's rings cast wide shadows on the planet, and the shadow of a moon also graces the gas giant in this scene from NASA's Cassini spacecraft. The moon Enceladus is not shown in this view, but it does cast a small, elongated shadow.
Bright spokes and the shadow of a moon grace Saturn's B ring in this NASA Cassini spacecraft image. Spokes are radial markings scientists continue to study, and they can be seen here stretching from the far left to upper right of the image.
Shadows adorn Saturn in this view from NASA's Cassini spacecraft, which also includes the moon Rhea, shown orbiting between the planet and the spacecraft and appears above the rings on the left of the image.