Space · Moons

Sycorax

A moon of Uranus — The largest of Uranus's outer irregular moons.

Quick facts

Parent planet

Uranus

Diameter (mean)

165 km

Mass

2.5 × 10¹⁸ kg
3.4e-05 Moon masses

Mean orbital radius

12,179,000 km

Orbital period

1288.3 Earth days

Discovery year

1997

Discoverer

Philip D. Nicholson, Brett J. Gladman et al.

Naming origin

Witch in The Tempest, mother of Caliban

Surface conditions

Sycorax is the largest of Uranus's irregular outer moons, a captured body 165 km across in a highly inclined retrograde orbit. The deep red surface color is typical of Centaur and Kuiper Belt objects, consistent with capture from the outer solar system.

Missions and observations

Every Uranus-system mission has had an opportunity to image or characterize Sycorax. The list below is the Uranus-system mission catalog; specific Sycorax encounters are documented in mission archives.

Mission Year at Uranus Status

Voyager 2

NASA

1986 Completed

Naming etymology

Sycorax was the absent mother of Caliban and former ruler of the island in Shakespeare's The Tempest, mentioned but never seen. Adopted by the IAU in 1998.

Methodology & sources

Diameter, mass, and orbital parameters from JPL Solar System Dynamics — Physical Parameters. Discovery year and discoverer from the JPL Satellite Discovery Circumstances. Naming etymology from the IAU Working Group for Planetary System Nomenclature. Stylized SVG hero composed from NASA / JPL imagery as visual reference; no photographs are reproduced.

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