A new study finds that as early as 3,100 years ago, the Olmecs and Mayans who lived along Mexico’s Gulf Coast built star-lined ritual centers to track important days in a 260-day calendar.
This Earliest written evidence of this calendarfound on fragments of painted plaster murals at Mayan sites in Guatemala, dated to between 300 BC and 200 BC, nearly a millennium later (Serial Number: 22/4/13). But researchers have long suspected that the Olmec peoples of the Gulf Coast had developed a 260-day calendar hundreds of years earlier.
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Now, an airborne laser-mapping technology called light detection and ranging, or lidar, has revealed Astronomical Orientation of the 415 Ceremonial Complexes Archaeologist Ivan Šprajc and his colleagues say the date is somewhere between 1100 BC and 250 AD.Most ritual centers are aligned on an east-west axis that corresponds to sunrise or other celestial events on specific days of the year’s 260 days, the scientists reported Jan. 6. scientific progress.
The discovery points to the earliest evidence of a formal calendar system in the Americas that combines astronomical knowledge with Earth’s structure. The system uses celestial events to identify important dates in a 260-day year.
“The 260-day cycle is materialized in the earliest known monumental complex in Mesoamerica [and was used] used to arrange seasonal, subsistence-related rituals,” says Šprajc of the Research Center of the Slovenian Academy of Sciences and Arts in Ljubljana. “We cannot say for sure when and where it was invented. “
Stephen Houston, an archaeologist at Brown University in Providence, Rhode Island, who was not involved in the new study, said some of the oldest ritual centers identified by lidar clearly belonged to the Olmec culture, but others were harder to classify .
Olmec society dates back approximately 3,500 to 2,400 years ago. The connection between the Olmec culture and the later Maya culture, known for flourishing Classical-era cities and kingdoms about 1,750 to 1,100 years ago, is unclear. But classic Mayan inscriptions and documents also refer to the 260-day calendar.
Šprajc and colleagues suggest that in Mesoamerica, an ancient cultural region stretching from central Mexico to Mesoamerica, mobile groups may have used the 260-day calendar to arrange large seasonal gatherings long before the 260-day calendar gained favor with classical Mayan kings. The same calendar may also mark days of important agricultural events or rituals as maize cultivation spread across Mesoamerica starting about 3,000 years ago, they add. Some Mayan communities still use a 260-day calendar to organize corn planting and arrange agricultural rituals.
Previous lidar data showed that Ritual centers based on common blueprints appear at many Olmec and Mayan sites About 3,400 years ago the Gulf Coast (Number: 10/25/21). It is only now that the calendar significance of the ritual central arrangement becomes apparent.
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The most common building alignments detected in the new study corresponded to the positions of the sunrises on February 11 and October 29, when the complex was in use, 260 days apart. The complexes face east, toward a point on the horizon where the sun rises on those two days.
The other frequent direction matches half of the sunrises counted 130 or 260 days apart.
A few ritual complexes are aligned with the solstices (the longest and shortest days of the year), the quarters (the midpoints of each half-year of the year), or the 260-day lunar cycle of the year. Other centers tracked the position of Venus, a star associated with the rainy season and the cultivation of corn.
Sunrises or sunsets recorded at the center of the ceremony are usually separated by multiples of 13 or 20 days. In addition to representing the basic mathematical unit of 260 days in a year, the numbers 13 and 20 have long been associated with various deities and sacred concepts of the Mayans and other Mesoamerican groups, Šprajc said.
Future excavations in ritual complexes detected by lidar could investigate whether ancient groups formally used certain structures for specific days of the 260-day year, Houston said.