In 2011 and 2012, two new moons were discovered in orbit around Pluto. Called P4 and P5, the scientists who discovered the moons have put up a poll asking internet users to select from one of twelve names (or to write in a suggestion) as to what the moons should be called. The choices, all of which have a mythical tie to the underworld, are Acheron, Alecto, Cerberus, Erebus, Eurydice, Hercules, Hypnos, Lethe, Obol, Orpheus, Persephone, and Styx.
Scientists have announced the discovery of a fourth moon in orbit around Pluto. Pluto’s first discovered moon, Charon, was found in 1978. Two more moons, Nyx and Hydra, were identified in 2005. The new moon, which is currently called P4, is believed to be between 13 and 34 km in diameter and orbits Pluto every 32 days at a distance of about 59,000 km, between the orbits of Nyx and Hydra.
Astronomer Mike Brown is seeking suggestions for the moon in orbit around Kuiper Belt Object Orcus. The moon, discovered in 2005, currently bears the less than memorable designation “S/1 90482 (2005).” In his description of the object, Brown notes that Orcus is named for the Etruscan god of the dead, who was subsumed into the Roman Pluto.