Saturn, the ringed giant planet, has a large satellite family, consisting of 62 moons and numerous smaller objects, known as moonlets. NASA recently published a wonderful image of Saturn, acquired by the Saturn-orbiting Cassini spacecraft. The image shows a wonderful view of the Saturn’s rings and five Saturnian moons.
The moons are, in order of size, Rhea (1,528 km across), Enceladus (504 km across), Mimas (396 km across), Janus (179 km across) and Pandora (81 km across). (The names of these moons come from Greek mythology. Most of the Solar System’s moons have mythologies names.)
Saturn’s satellites vary widely in size. The largest moon is Titan (5,150 km across), while the moonlets are less than 1 km across. Titan is the second largest planetary moon, after Ganymede (5,250 km across), Jupiter’s giant satellite. Except for Titan, Saturn’s moons are all smaller than Earth’s Moon (3,476 km across).
Rhea, Saturn’s second largest moon, is visible on the far right of the image, bisected by image’s frame. Mimas is adjacent to Rhea, while Janus is on the far left. Pandora appears between two rings, near image’s center. Enceladus shines above center. It is the brightest body in the image, since it has a highly reflective surface, which reflects most of incident sunlight.
The image was taken by Cassini’s narrow-angle camera, on 29 July 2011. Cassini was just above the plane of the rings, at a distance of approximately 1.1 million km from Rhea.
References
NASA
www.nasa.gov/
Further Reading
Cassini Mission Websites
http://www.nasa.gov/cassini
http://saturn.jpl.nasa.gov