Charons

Charons may refer to two widely cited uses of the name Charon: the mythological ferryman of the dead in ancient Greece, and the largest moon of Pluto.

In Greek mythology, Charon is the ferryman who transports souls across the river Styx or Acheron to the realm of Hades. Souls typically required a coin, the obol, paid to Charon at burial to secure passage; those without such a payment were thought to drift at the river’s edge or be denied crossing. Charon's imagery appears in ancient literature and art as a grim, gaunt boatman who operates a small ferry crossing the underworld. The character is sometimes described as a daemon rather than a god and is discussed in works attributed to Hesiod, Homer, and later writers. The stories vary on parentage and detail, but Charon’s function remains a threshold role between life and death.

In astronomy, Charon is the largest moon of the dwarf planet Pluto. It was discovered in 1978 by James W. Christy using ground-based observations and later studied in more detail by the New Horizons mission in 2015. Charon has a diameter of about 1,200 kilometers and orbits Pluto at a distance of roughly 19,600 kilometers. The Pluto-Charon system is nearly a binary; the barycenter lies outside Pluto, and the two bodies are tidally locked to each other. Charon has a complex surface with various tectonic features and possibly a subsurface ocean. It is one of five known moons of Pluto; others include Hydra, Nix, Kerberos, and Styx.