Umbriel

views updated May 08 2018

Umbriel (Uranus II) One of the major satellites of Uranus. Its mean radius is 584.7km; mass 11.72 × 1020 kg; mean density 1400 kg/m3; albedo 0.18. The surface is evenly cratered and darker than the other four major satellites, except for a bright ring 4 km in diameter. The many large craters suggest the surface is old.

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