Although we are used to seeing Saturn's moons lit directly by the Sun, sometimes we can catch them illuminated by 'Saturnshine.' Here, NASA's Cassini spacecraft see Mimas (upper right) lit by light reflected off of Saturn.
From afar, Saturn's rings look like a solid, homogenous disk of material. But upon closer examination from NASA's Cassini spacecraft, we see that there are varied structures in the rings at almost every scale imaginable.
NASA's Cassini orbiter shows Saturn is circled by its rings (nearly edge-on in this image), as well as by the moons Tethys (the large bright body near the lower right corner) and Mimas (seen as a slight crescent against Saturn's disk above the rings).
NASA's Cassini spacecraft spies Mimas, positioned against the shadow of Saturn's rings, bright on dark. As we near summer in Saturn's northern hemisphere, the rings cast ever larger shadows on the planet.
Among the interplay of Saturn's shadow and rings, Mimas, which appears in the lower-right corner of the image, orbits Saturn as a set of the ever-intriguing spokes appear in the B ring (to the right of center) in this image from NASA's Cassini spacecraft.
This image from NASA's Cassini spacecraft reminds us of how different Mimas and Pandora are when they appear together; although both are moons of Saturn, Pandora's small size means that it lacks sufficient gravity to pull itself into a round shape.
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.
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!
Scientists with NASA's Cassini mission have spotted two features shaped like the 1980s video game icon "Pac-Man" on moons of Saturn. One was observed on the moon Mimas in 2010 and the latest was observed on the moon Tethys.
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.
The shadow of the moon Mimas creates a smudge on the southern hemisphere of Saturn in this view from NASA's Cassini spacecraft. Mimas does not appear here, but it does cast its shadow on the planet in the lower left of the image.