Online Astronomy eText: Satellites (Moons)
The Satellites (Moons) of Saturn: Epimetheus Link for sharing this page on Facebook
(mostly written in 2004, before the Cassini spacecraft reached Saturn)

Photograph by Voyager 1 in 1980. The dark line on the left is the shadow of the F ring of Saturn.

(False-color) composite image by Cassini spacecraft (March, 2005).
(Cassini Imaging Team, SSI, JPL, ESA, NASA, apod050429)

Another image of Epimetheus, taken during the July, 2005 Cassini flyby.
(Cassini Imaging Team, SSI, JPL, ESA, NASA, apod050824)

Data for Epimetheus

Discovered by R. Walker in 1980
Named after one of the sons of Iapetus
Orbital size 151,472 km (about 94,000 miles) (co-orbital with Janus)
Orbital eccentricity 1%
Orbital inclination 0.3 degrees
Orbital period 16.6 hours
Rotation period 16.6 hours (synchronous, one side always faces Saturn)
Diameter 145 x 110 x 100 km (about 90 x 67 x 60 miles)
Mass, density and surface gravity very uncertain
Albedo (reflectivity) 80%