Space · Moons

Halimede

A moon of Neptune — An outer retrograde Neptunian irregular.

Quick facts

Parent planet

Neptune

Diameter (mean)

62 km

Mass

1.6 × 10¹⁷ kg
2.2e-06 Moon masses

Mean orbital radius

16,611,000 km

Orbital period

1879.7 Earth days

Discovery year

2002

Discoverer

Matthew J. Holman et al.

Naming origin

One of the Nereids

Surface conditions

Halimede is a retrograde outer irregular moon of Neptune, about 62 km across. The color is similar to Nereid's, suggesting a possible common origin or composition.

Missions and observations

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

Mission Year at Neptune Status

Voyager 2

NASA

1989 Completed

Naming etymology

Halimede was one of the 50 Nereid sea nymphs of Greek mythology. Adopted by the IAU in 2007.

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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