Tethys

Definition

Astronomy

  • satellite of Saturn discovered in 1684 by Cassini. Tethys orbits Saturn in a circular 1.9 day orbit 295 000km from the planet and is just over 500km across. With a density close to 1gm/cc, Tethys consists mainly of ice. Its surface is heavily cratered and features deep, wide valleys, the latter being regarded as evidence of past geological activity.
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