NASA’s Cassini robotic orbiter captured this incredible view of Epimetheus, an inner satellite of Saturn, during a flyby on February 21, 2017. The flyby had a close-approach distance of 9,300 miles (15,000 km).
This image of Saturn’s moon Epimetheus was taken with Cassini’s narrow-angle camera on February 21, 2017, using a spectral filter which preferentially admits wavelengths of near-infrared light centered at 939 nm. Image credit: NASA / JPL-Caltech / Space Science Institute.
Epimetheus is a potato-shaped object with dimensions approximately 84 x 65 x 65 miles (135 x 108 x 105 km, respectively).
Also known as Saturn XI and S/1980 S3, the small moon was discovered by astronomer Richard Walker on December 18, 1966.
Epimetheus is phase locked with Saturn — one side always faces toward the gas giant.
It orbits 94,000 miles (151,000 km) away from the planet, taking 17 hours to circle the gas giant, in the gap between the F and G rings, but it doesn’t do this alone.
Epimetheus and the neighboring Saturnian moon Janus have been referred to as the Siamese twins of Saturn because they orbit the parent planet in nearly the same orbit.
These two moons may have formed by the break-up of one object.
Epimetheus is too small for its gravity to hold onto an atmosphere.
It is also too small to be geologically active. There is therefore no way to erase the scars from meteor impacts, except for the generation of new impact craters on top of old ones.
Epimetheus is thought to be composed of water ice, but its density of less than 0.7 is much less than that of water.
Thus, the moon is probably a collection of numerous boulders, rocks, and dust.
While Cassini captured this close-up view of Epimetheus with a narrow-angle camera on February 21, the Cassini science team only released the photo last week.
The spacecraft was about 9,300 miles away from Epimetheus when it captured the view.
