The moons visible in this image from NASA's Cassini spacecraft, Pandora and Atlas, are quite small by astronomical standards, but the rings are also enormous. From one side of the planet to the other, the A ring stretches over 170,000 miles (270,000 km).
NASA's Cassini spacecraft captures a rare family photo of three of Saturn's moons that couldn't be more different from each other. Shown here are Tethys (center), Hyperion (upper left), and Prometheus (lower left).
NASA's Voyager 2 spacecraft flew by Triton, a moon of Neptune, in the summer of 1989. Dr. Paul Schenk, a scientist at the Lunar and Planetary Institute in Houston, used Voyager data to construct the best-ever global color map of Triton.
This image from NASA's Cassini spacecraft, one of those acquired in the survey conducted by the Cassini imaging science team of the geyser basin at the south pole of Enceladus, was taken as Cassini was looking across the moon's south pole.
Seen by NASA's Cassini spacecraft, Tethys, like many moons in the solar system, keeps one face pointed towards the planet around which it orbits. Tethys' anti-Saturn face is seen here, fully illuminated, basking in sunlight.
As seen by NASA's Cassini spacecraft, the surface of Dione is covered in craters, reminding us of the impacts that have shaped all of the worlds of our solar system; the surface also bears linear features that suggest geological activity in the past.
Only a sharp and careful eye can make out the subtle variations in Titan's clouds when viewed in visible light by NASA's Cassini spacecraft. This infrared image clearly reveals a band around the Titan's north pole.
The image on the left shows Cassini's view on approach to Phoebe, while the right shows the spacecraft's departing perspective. As it entered the Saturn system, NASA's Cassini spacecraft performed its first targeted flyby of one of the planet's moons.
Prometheus is caught in the act of creating gores and streamers in the F ring. Scientists believe that Prometheus and its partner-moon Pandora are responsible for much of the structure in the F ring as shown by NASA's Cassini spacecraft.
Tethys' trailing side shows two terrains that tell a story of a rough past. To the north (up, in image) is older, rougher terrain, while to the south is new material dubbed 'smooth plains' by scientists. This image was taken by NASA's Cassini spacecraft.
This view from NASA's Cassini spacecraft features a blue planet, Uranus, imaged by Cassini for the first time. Uranus is a pale blue in this natural color image because its visible atmosphere contains methane gas and few aerosols or clouds.
Saturn's moon Prometheus orbits near some of its handiwork in the F ring in this image from NASA's Cassini spacecraft. Prometheus and its partner Pandora gravitationally sculpt and maintain the narrow F ring.
Saturn's D ring is easy to overlook since it's trapped between the brighter C ring and the planet itself. In this view from NASA's Cassini spacecraft, all that can be seen of the D ring is the faint and narrow arc as it stretches from top right of the ima