A moon of Saturn discovered by Pascu, Seidelmann, Baum and Currie in 1980 from ground-based observations. Calypso is co-orbital with the moon Tethys, and resides in Tethys' trailing Lagrangian point (L5). The moon Telesto resides in Tethys' leading Lagrangian point.
- Orbital radius: 294,660 km
- Diameter: 26 km (34 x 22 x 22)
- Mass: Unknown
- Orbital period: 1.8878 days
- Orbital inclination: 0°