Pluto Moons (5)


Pluto has 5 known moons. Pluto’s entire moon system is believed to have formed by a collision between the dwarf planet and another Kuiper Belt Object early in the history of the solar system.

1. Charon 2. Nix 3. Hydra 4. Kerberos 5. Styx

Name Charon
Discovery date 1978 (James Walter Christy)
Semi-major axis 19 571.4 km
Diameter 1208 km
Orbital period
(Length of a year)
6.3872304 Earth days
Charon. Photo: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

Name Nix
Discovery date 2005 (Hal A. Weaver, S. Alan Stern, Max J. Mutchler, Andrew J. Steffl, Marc W. Buie, William J. Merline, John R. Spencer, Eliot F. Young, und Leslie A. Young)
Semi-major axis 48 675 km
Diameter ~ 42 x 36 km
Orbital period
(Length of a year)
24.8562 Earth days
Nix. Photo: NASA/JHUAPL/SWRI

Name Hydra
Discovery date 2005 (Hal A. Weaver, S. Alan Stern, Max J. Mutchler, Andrew J. Steffl, Marc W. Buie, William J. Merline, John R. Spencer, Eliot F. Young, und Leslie A. Young)
Semi-major axis 64 780 km
Diameter ~ 55 x 40 km
Orbital period
(Length of a year)
38.2065 Earth days
Hydra. Photo: NASA/JHUAPL/SwRI

Name Kerberos
Discovery date 2012 (Mark R. Showalter et al.)
Semi-major axis 59 000 km
Diameter ~ 12 x 4.5 km
Orbital period
(Length of a year)
32.1 Earth days
Kerberos. Photo: NASA/JHUAPL/SwRI

Name Styx
Discovery date 2011 (Mark R. Showalter et al.)
Semi-major axis 42 000 km
Diameter ~ 7 x 5 km
Orbital period
(Length of a year)
20.2 Earth days
Styx. Photo: NASA/JHUAPL/SwRI