An Etymological Dictionary of Astronomy and Astrophysics

The fifth confirmed → satellite of → Pluto discovered in 2012 using a set of the → Hubble Space Telescope. Also called Pluto V (P5). It orbits Pluto between → Charon and → Nix at a distance of about 42,000 km.
Styx is estimated to have a diameter of between 10 and 30 km, and an → orbital period of 20.2 days.

See also: Named for the Greek mythological river that separates the world of the living from the realm of the dead.