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Saturn XIV, Tethys C

Proper NameCalypso
DesignationSaturn XIV
Primary PlanetSaturn
Orbital Period1 day, 21 hours, 18 minutes
Distance from SaturnSemi-Major Axis: 294,619 km
Periapsis: 292,527 km
Apoapsis: 296,711 km
Rotation Period1 day, 21 hours, 18 minutes (synchronous orbit)
Diameter (longest axis)30.2 km
18.8 miles
NotesCalypso has a long, narrow shape, just over thirty kilometres along its longest axis, but only fourteen across its shortest diameter. Its surface is marked by several relatively large craters, but particles from Saturn's E Ring have filled these craters and smoothed their edges.

One of three moons that share an orbit of Saturn nearly 300,000 km from the planet within the tenuous and icy ring known as the E Ring. The largest of these three is Tethys, a spherical moon more than a thousand kilometres in diameter, but Tethys also has two smaller companions. Calypso is one these, a fraction of Tethys' size and following that major moon in its orbit around Saturn by some sixty degrees of arc. It is able to hold a stable relative position because it occupies Tethys' trailing Lagrange Point. Calypso has a counterpart, Telesto, which precedes Tethys in its orbit by the same sixty degree angle that Calypso trails behind.

Physically Calypso is an irregular body, highly elongated in shape; it measures a little more than thirty kilometres along its longest axis, and less than fifteen kilometres along its shortest. Though rocky and cratered, its surface is also relatively smooth, with a tracery of flowing patterns. These effects are probably due to particles collected from the enveloping E Ring, particles whose ultimate origins lie in the great geysers blasting water ice outward from the moon Enceladus.


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