Tethys (pronounced TEE-this) is a large moon of the planet Saturn.
It was discovered by Giovanni Domenico Cassini in 1684. It was one of the first Saturnian moons discovered.
[change] Physical Characteristics
[change] Mass, Density and Volume
Tethys' mass is 617,551,805,221,061,000,000 kg, its density is 0.973 g/cm3 and its volume is 634,264,255 km3.
[change] Craters and Valleys
It has a very large crater on its surface, called Odysseus. It is named after a Greek warrior king in Homer's two great works, The Iliad and The Odyssey. There is also a very long valley called Ithaca Chasma. It is 100 km wide and 2000 km long.
[change] Orbit and Rotation
Tethys takes 45.3 hours to orbit (go around) Saturn and orbits Saturn 294,660 km away. Tethys is tidally locked in phase with its parent planet - one side always faces toward Saturn.