90482 Orcus Etruscan equivalent of the Roman Pluto, and later became an alternate name for Pluto. The surface of Orcus is relatively bright with albedo reaching 23%, grey in color and water-rich. The ice is predominantly in crystalline form, which may be related to past cryovolcanic activity. Other compounds like methane or ammonia may also be present. The existence of a satellite allowed astronomers to determine the mass of the system, which is approximately equal to that of the Saturnian moon Tethys. The ratio of masses of Orcus and Vanth is uncertain, possibly anywhere from 1:33 to 1:12. The diameter of Orcus
Dis (Divine Comedy) halls and vacant realm of Dis" with his guide, the Sibyl, who correspond in "The Divine Comedy" to "Dante" as the speaker of the poem and his guide, Virgil. The walls of Dis are guarded by fallen angels, the Furies, and Medusa. Dante emphasizes the character of the place as a city by describing its architectural features: towers, gates, walls, ramparts, bridges, and moats. It is thus an antithesis to the heavenly city, as for instance described by St. Augustine in his book "City of God". Among these structures are mosques, "the worship places of the most dangerous enemies of