Charon

Charon is the largest satellite of the dwarf planet Pluto. It was discovered in 1978 at the United States Naval Observatory Flagstaff Station (NOFS). Following the 2005 discovery of two other natural satellites of Pluto (Nix and Hydra), in 2011, a fourth, Kerberos, and on July 11, 2012, a fifth satellite Styx, Charon may also be referred to as (134340) Pluto I. The New Horizons mission is scheduled to visit Charon and Pluto in July 2015.