Saturn may be a sight to see, but its small moon Epimetheus has had a hard-knock life.

In this false-color view, the Cassini spacecraft offers the closest look yet at Epimetheus, an apparently battered satellite orbiting 94,090 miles (151,422 km) away from its ringed parent.

Cassini used a series of filters to scan Epimetheus in the ultraviolet, polarized green and infrared portions of the light spectrum, then combined them to generate the surface colors seen here. Typically, such hue differences are a sign of regional variations in the chemical make-up of the surface, though they can also be caused by the unique reflectivity of different materials.

Astronomers believe that it is the reflectivity of Epimetheus’s surface materials – dubbed the photometric effect - that is the source of its rainbow-like appearance, citing the increase in blue tones in areas where sunlight hits at greater angles.

Here, the crater Pollox appears as a slightly reddish blotch in the lower left, while just below the moon’s center is Hilairea, a 21-mile (33-kilometer) wide crater awash in shadow.

With a diameter of 72 miles (116 kilometers), Epimetheus is slightly smaller than its satellite companion Janus – 113 miles (181 kilometers) across - which orbits at essentially the same distance from Saturn.

Cassini used its narrow-angle camera to obtain this image on March 30, 2005, while skirting past Epimetheus at a distance of 46,350 miles (74,600 kilometers). Resolution for each of the original images was about 1,480 feet (450 meters) per pixel. This view shows an area seen only very obliquely by NASA's Voyager spacecraft and has been magnified by two to aid visibility. The image has also been rotated so that north on Epimetheus is up.

-- SPACE.com Staff

Credit: NASA/JPL/Space Science Institute