42355 Typhon
42355 Typhon is a scattered disc object that was discovered on February 5, 2002, by the NEAT program. It measures 162±7 km in diameter, and is named after Typhon, a monster in Greek mythology.
Typhon is the first known binary centaur, using an extended definition of a centaur as an object on a non-resonant orbit with the perihelion inside the orbit of Neptune.Moon
A large moon was identified in 2006. It is named Echidna, after the monstrous mate of Typhon. It orbits Typhon at ~1300 km, completing one orbit in about 11 days. Its diameter is estimated to be 89±6 km.
