Saturn's Moons: Contrasting Crescents

Credit: NASA/JPL-Caltech/Space Science Institute

In this view, Saturn’s icy moon Rhea passes in front of Titan as seen by NASA’s Cassini spacecraft. Some of the differences between the two large moons are readily apparent. While Rhea is a heavily-cratered, airless world, Titan’s nitrogen-rich atmosphere is even thicker than Earth’s.


This natural color image was taken in visible light with the Cassini narrow-angle camera on Nov. 19, 2009, at a distance of approximately 713,300 miles (1,148,000 kilometers) from Rhea.


The Cassini spacecraft ended its mission on Sept. 15, 2017.

Source / Image Courtesy

 

For nearly two years, the orbital path of NASA's Cassini spacecraft has limited the mission's encounters with Saturn's moons.

The two views of Rhea were taken about an hour-and-a-half apart on Feb. 9, 2015, when Cassini was about 30,000 to 50,000 miles (50,000 to 80,000 kilometers) away from the moon.

Rhea is Saturn’s second-largest moon, and had the distinction of being the most heavily-cratered body in the solar system.

In natural color, the moon's surface is fairly uniform. The image at right represents the highest-resolution color view of Rhea released to date.

 

Saturn’s giant, hazy moon Titan has been essential to NASA’s Cassini mission during its 13 thrilling years of exploration there. Cassini and the European Huygens probe have revealed a fascinating world of lakes and seas, great swaths of dunes, and a complex atmosphere with weather – with intriguing similarities to Earth. Titan has also been an engine for the mission, providing gravity assists that propelled the spacecraft on its adventures around the ringed planet.

 

On Jan. 14, 2005, ESA's Huygens probe made its descent to the surface of Saturn's hazy moon, Titan. Carried to Saturn by NASA's Cassini spacecraft, Huygens made the most distant landing ever on another world, and the only landing on a body in the outer solar system. This video uses actual images taken by the probe during its two-and-a-half hour fall under its parachutes.

Huygens was a signature achievement of the international Cassini-Huygens mission, which will conclude on Sept. 15, 2017, when Cassini plunges into Saturn's atmosphere.