![]() Calypso image from Cassini
(February 13, 2010) |
|
Discovery | |
---|---|
Discovered by |
|
Discovery date | March 13, 1980 |
Designations | |
Adjectives | Calypsonian |
Orbital characteristics | |
619 km 294 | |
Eccentricity | 0.000 |
802 d 1.887 | |
Inclination | 1.56° (to Saturn's equator) |
Satellite of | Saturn |
Physical characteristics | |
Dimensions | 30.2 × 23 × 14 km |
Mean radius
|
±0.7 km 10.7 |
synchronous | |
zero | |
Albedo | ±0.10 1.34(geometric) |
Calypso (/kəˈlɪpsoʊ/ kə-LIP-soh; Greek: Καλυψώ) is a moon of Saturn. It was discovered in 1980, from ground-based observations, by Dan Pascu, P. Kenneth Seidelmann, William A. Baum, and Douglas G. Currie, and was provisionally designated S/1980 S 25 (the 25th satellite of Saturn discovered in 1980). Several other apparitions of it were recorded in the following months: S/1980 S 29, S/1980 S 30,S/1980 S 32, and S/1981 S 2. In 1983 it was officially named after Calypso of Greek mythology. It is also designated as Saturn XIV or Tethys C.
Calypso is co-orbital with the moon Tethys, and resides in Tethys' trailing Lagrangian point (L5), 60 degrees behind Tethys. This relationship was first identified by Seidelmann et al. in 1981. The moon Telesto resides in the other (leading) Lagrangian point of Tethys, 60 degrees in the other direction from Tethys. Calypso and Telesto have been termed "Tethys trojans", by analogy to the trojan asteroids, and are half of the four presently known trojan moons.