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,
90482 Orcus a result of rotational fission of the primordial Orcus, which would have rotated much faster than now. On 23 March 2009, Brown asked readers of his weekly column to suggest possible names for the satellite, with the best one to be submitted to the International Astronomical Union (IAU) on 5 April. The name Vanth, after the Etruscan goddess who guided the souls of the dead to the underworld, was eventually chosen from among a large pool of submissions. This submission was assessed by the IAU's Committee for Small Body Nomenclature, which voted to approve it in March 2010, in accordance