AZTEC CALENDAR

dating system that combines the tonalpohualli, a ritual cycle of 260 days, with the solar year of 365 days. Like the Mayan calendar from which it was derived, the Aztec calendar consisted of a ritual cycle that was divided into 13 periods of 20 days each and a civil cycle that was divided into 18 months of 20 days plus an additional 5 days, called nemontemi, considered to be very unlucky. Again as in the Mayan calendar, the Aztec ritual and civil cycles returned to the same positions relative to each other every 52 years, an event celebrated as the Binding Up of the Years, or the New Fire Ceremony. In preparation, all sacred and domestic fires were allowed to burn out. At the climax of the ceremony, priests ignited a new sacred fire on the breast of a sacrificial victim, from which the rest of the people rekindled their hearth fires and began feasting. Aztec Calendar Stone. The calendar, discovered in 1790, is a basaltic monolith. It A circular calendar stone measuring 3.7 m (about 12 feet) in diameter and weighing some 25 tons was uncovered in Mexico City in 1790 and is currently on display in the National Museum of Anthropology in Mexico City. The face of the Aztec sun god, Tonatiuh, appears at the centre of the stone, surrounded by four square panels honouring previous incarnations of the deity that represent the four previous ages of the world. Circumscribing these are signs that represent the 20 days of the Aztec month.