nemontemi

Mesoamerican almanac

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July 16, 2026

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The term "nemontemi" refers to the five unlucky days at the end of the Aztec 365-day solar year. These days were considered dangerous and were a time when people avoided important activities.1

The Mesoamerican calendar system also included the tonalpohualli, a 260-day sacred almanac used by cultures like the Maya, Mixtec, and Aztec. This almanac was formed by combining numbers 1-13 with 20 day names, creating a cycle of 260 unique days. The tonalpohualli was used for scheduling rituals and for divination, with priests consulting it to determine auspicious days for significant undertakings or to name newborns.21

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Aztec calendar
…an additional 5 days called nemontemi and 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…
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…an additional 5 days called nemontemi and 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…
Read More