The Maya and Aztec calendars were primarily based on which celestial body?

The Maya and Aztec calendars were primarily based on the Sun. Both civilizations developed complex calendrical systems that incorporated solar cycles. The Maya, for instance, used a solar calendar known as the Haab', which consisted of 365 days and was aligned closely with the solar year. This calendar organized the agricultural cycle crucial for farming and societal planning. Similarly, the Aztec calendar, which included the Tonalpohualli (a 260-day ritual calendar) and the Xiuhpohualli (a 365-day solar calendar), also revolved around the solar year, reflecting their deep understanding of solar movements.

The focus on the Sun in these calendars illustrates the significance of solar cycles in their agricultural practices, religious events, and daily life, underpinning their culture and sciences. While other celestial objects such as the Moon and stars played roles in Mesoamerican cosmology and may have influenced some aspects of timekeeping, the primary structure of their calendars relied heavily on the solar year. This reliance on solar cycles highlights the essential role of the Sun not only in Mesoamerican agricultural society but also in their spiritual worldview.