The largest of Pluto's five moons, Charon, was discovered in June 1978 by James Christy and Robert Harrington at the U.S. Naval Observatory in Flagstaff, Arizona―only about six miles from where Pluto itself was discovered at Lowell Observatory.  At half the size of Pluto, Charon is the largest of Pluto's moons and the largest known satellite relative to its parent body. Pluto-Charon is our solar system's only known double planetary system. The same surfaces of Charon and Pluto always face each other, a phenomenon called mutual tidal locking. Charon orbits Pluto every 6.4 Earth days.

Charon

PDS Image Atlas

Cross-mission and cross-instrument searches for images and spectra from Cassini, Voyager 1 and 2, Galileo, New Horizons, and the Hubble Space Telescope

Outer Planets Unified Search

New Horizons is a robotic spacecraft mission conducted by NASA. It was the first spacecraft to fly by and study the dwarf planet Pluto and its moons, Charon, Nix and Hydra. After the successfull flyby of Pluto, the spacecraft continued on for a Jan 2019 flyby of as part of the New Horizons Kuiper Belt Extended Mission (KEM). The mission was prepared primarily by Southwest Research Institute (SwRI) and the Johns Hopkins Applied Physics Laboratory (APL). New Horizons was successfully launched on January 19, 2006. After a flyby of Jupiter on February 28, 2007 at 5:43:40 UTC, New Horizons is expected to arrive at Pluto in July 2015. As New Horizons passed through the Jovian system for a gravity assist in February, it performed scientific observations of Jupiter, the Galilean satellites, the Jovian rings, Himalia, Elara, and Earth.

Charon Information Page

Mission Data

Observational data produced from a Mission or Investigation

New Horizons