90482 Orcus This means that Orcus is currently viewed pole-on, which could explain the near absence of any rotational modulation of its brightness. If, however, the primary is tidally locked with the satellite, the rotational period will coincide with the 9.7-day orbital period of Vanth. This minor planet was named after one of the Roman gods of the underworld, Orcus. While Pluto was the ruler of the underworld, Orcus was a punisher of the damned. The approved naming citation was published by the Minor Planet Center on 26 November 2004 (). Under the guidelines of the International Astronomical Union's (IAU) naming conventions,
Orcus Orcus Orcus () was a god of the underworld, punisher of broken oaths in Italic and Roman mythology. As with Hades, the name of the god was also used for the underworld itself. In the later tradition, he was conflated with Dis Pater. Orcus was portrayed in paintings in Etruscan tombs as a hairy, bearded giant. A temple to Orcus may have existed on the Palatine Hill in Rome. It is likely that he was transliterated from the Greek daemon Horkos, the personification of Oaths and a son of Eris. The origins of Orcus may have lain in Etruscan religion.