Moon of Saturn
Tethys
An icy moon that shares its orbit with two tiny companions.
Tethys circles Saturn every 45.3 hours on an essentially circular path, always showing the same face. Two small moons, Telesto and Calypso, ride in its orbit 60 degrees ahead and behind, held at stable Lagrange points. The three travel around Saturn as a unit.
How it moves
- Tethys orbits Saturn every 1.888 days (45.3 hours) at about 294,660 km.
- Its listed eccentricity is 0.0000, an essentially circular orbit.
- Telesto and Calypso share Tethys's orbit at its L4 and L5 Lagrange points, 60 degrees ahead and behind.
- Tethys is tidally locked to Saturn.
Facts
- Mean radius
- 531.1 km
- Mass
- 6.180e+20 kg
- Surface gravity
- 0.146 m/s²
- Rotation period
- 45.307 hours
- Orbital period
- 1.888 days
- Average orbital distance
- 294,660 km
- Eccentricity
- 0
- Discovered
- March 21, 1684, by Giovanni Domenico Cassini
Tethys shares its orbit with two small moons that travel 60 degrees ahead and behind it.
Sources: nssdc.gsfc.nasa.gov, ssd.jpl.nasa.gov, ssd.jpl.nasa.gov