Rhea

Definition

Astronomy

  • satellite of Saturn discovered by Cassini in 1672. Rhea has a circular, 4.5 day orbit almost exactly in the plane of Saturn’s equator and 527,000km in radius. Rhea is a bright, icy world with impact craters dominating its surface, and is some 1500km across with a density of only about 1.3, implying that it consists mainly of ice mixed with a little rock.
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