Researchers in Mexico have discovered that an ancient Mayan observatory isn't only aligned to the sun, it's also designed to track the movement of the planet Venus across the sky, confirming that the ancient Central American civilization had extensive knowledge of astronomy and the solar system.
First unearthed at Acanceh in Mexico’s Yucatán peninsula in 2002, the observatory is thought to have been used in the Mayan’s early Classic period, between 300 and 600 AD, a millennia or more before the arrival of the Spanish in the Americas.
“We believe this building used to be a multifunctional facility that was used exclusively by the Mayan elite, specifically for priests-astronomers,” Beatriz Quintal Suaste, a researcher at the Yucatán National Institute of Anthropology and History (INAH), told the Mexico City newspaper Excelsior.
Doors in the structure align with the rising and setting of the sun during the spring and fall equinoxes, and the semicircular building is set up so that it casts no shadow in the midday sun.
That Venus, the brightest object in the sky after the sun and moon, was important to the priests-astronomers of Acanceh shows in how the southern edge of the observatory, which aligns with the planet's northernmost position in the night sky.
Quintal Suaste told Excelsior that the Mayans were able to track Venus' 584-day cycle through the night sky from the observatory, a hypothesis that's backed up by the text contained in three codexes that were found at the site.
A second researcher, Orlando Casares Contreras, told the paper, that the finding corroborates that Venus held an important cultural significance to the Mayas, whose civilization stretched from southern Mexico to Honduras. The planet was represented in their mythology by a god called Noh Ek.