small moon · moon of the dwarf planet Pluto
Nix
A small, elongated moon of Pluto found by Hubble in 2005, tumbling chaotically as it circles the Pluto–Charon pair.
- Distance from Earth today
- 5.35 billion km35.75 AU · light: 4 h 57 min
- Distance from the Sun today
- 5.33 billion km35.64 AU
- As of
- 3 November 2026position from NASA/JPL orbital elements
Where it is today
Top view of the plane of Earth’s orbit, compressed distance scale. Open on the big map with the time slider →
Facts
- Diameter
- 36.0 km
- Mass
- 0.0225 × 10¹⁸ kg
- Density
- 880 kg/m³
- Mean distance from the planet
- 49,300 km
- Orbital period
- 24.9 days
- Orbital eccentricity
- 0.015
- Orbital inclination
- 0.0°
Source of the figures: JPL SSD – Planetary Satellites (public domain).
Discovery: 2005 – Harold A. Weaver, S. Alan Stern et al. (Hubble Space Telescope)
Description
Nix is one of Pluto's four small moons, discovered together with Hydra in Hubble Space Telescope images taken in 2005 by a team led by Harold Weaver and Alan Stern. It orbits outside Charon, and because it circles a pair of massive bodies rather than a single one, its rotation is chaotic rather than steady. New Horizons photographed it in 2015, showing an elongated body with a bright, icy surface. Its name comes from Nyx, the Greek goddess of night and mother of Charon, the ferryman.