Systematic Sky Observation
The Mayan civilization, which flourished from approximately 2000 BCE to the 16th century, developed extraordinary astronomical knowledge comparable in accuracy to many later systems.
Their astronomy was integrated with ritual calendars, agriculture, politics, and religion, allowing them to calculate solar, lunar, and planetary cycles with remarkable precision.
The Role of Mayan Calendars
The Mayan system included several interconnected calendars: the 365-day Haab' for the solar year, the 260-day Tzolk'in for ritual purposes, and the Long Count for measuring large historical periods without repetition. This calendrical architecture was based on actual astronomical cycles and was adjusted through continuous observation of celestial bodies.
Precision in Measuring the Solar Year
Mayan astronomers calculated the duration of the solar year to be approximately 365.2420 days, a value very close to the modern value of 365.2422 days.
This precision was achieved without optical instruments, simply by observing the sun at the solstices and equinoxes year after year.
Prediction of Solar and Lunar Eclipses
The Mayans not only recorded solar and lunar eclipses but also developed tables to predict them accurately.
The Dresden Codex, a Mayan manuscript that survived colonial destruction, contains eclipse tables with repetitive cycles based on empirical observations that allowed them to anticipate celestial events decades or even centuries in advance.
Lunar Cycle and Phases of the Moon
The duration of the synodic lunar month (new moon to new moon) was calculated by the Mayans as 29.53 days, extremely close to the modern value of 29.5306 days.
This knowledge was key to predicting eclipses, marking fertility cycles, and establishing sacred dates, integrating with ceremonial and agricultural calendars.
Venus: The Most Studied Celestial Body
Among the celestial bodies, Venus played a central role in Mayan astronomy.
Associated with deities like Kukulcan and considered an omen of warlike phenomena or times of change, the Mayans recorded its synodic cycle of 583.92 days, equivalent to when Venus reappears as a morning or evening star.
The Dresden Codex includes a 104-year Venus table that demonstrates the great precision of these calculations.
Ritual and Social Use of Predictions
The predictions of eclipses, lunar cycles, and Venus positions were not merely scientific for the Mayans, but essential aspects of their cosmology and religiosity. These phenomena were interpreted as messages from the gods and determined activities such as wars, plantings, harvests, and ritual celebrations.
Buildings Aligned with Celestial Events
Mayan architecture reflects this astronomical knowledge. Structures like El Caracol in Chichén Itzá, known as observatories, are aligned with phenomena such as the trajectory of Venus or the solstices.
Likewise, many ceremonial centers have orientations that mark the sun's passage on key dates of the agricultural year.
Mayans and Agricultural Planning
Mayan astronomy was also used to plan agricultural activities, such as planting and harvesting dates.
The solstices and equinoxes, as well as the appearance of certain stars or planets, indicated propitious times for agriculture, directly related to the survival of their farming communities.
Dresden Codex: Essential Source of Astronomy
The Dresden Codex, composed of folded tree bark tablets and written around the 11th and 12th centuries, contains tables describing Venus cycles, eclipses, and solar and lunar cycles.
This codex is one of the few sources that have survived complete to the present day, offering direct evidence of Mayan astronomy.
Cosmovision and Fear of Certain Events
Although the Mayans valued and predicted celestial events, they also feared certain phenomena like eclipses, which were interpreted as cosmic imbalances or omens of crisis.
They prepared ceremonies to "appease" the deities and restore harmony, showing how astronomy was intertwined with religion and social stability.
