Despite being one of the most revered and prolific ancient cultures, the Maya civilisation is still shrouded in a veil of mystery. The Maya have many facets that have fascinated scholars and archaeologists for many years, from their architectural wonders to the complexity of their deities.
Overall, one of the most elusive elements of this civilisation has been the 819-day calendar—until now. The centuries-old mystery has now been solved, thanks to two Tulane University scientists who have finally figured out how the Mayan calendar works.
How much more? Forty-five years to be exact. "While previous studies aimed to show planetary relationships for the 819-day count, the four-part colour scheme is too short to match well with the synodic periods of the visible planets," the authors write. The key to the enigma lay in the number underlying the Mayan number system, i.e. base 20. “If the length of the calendar is increased to 20 periods of 819 days, a schema emerges in which the synodic periods of all visible planets are equivalent to park points on a larger 819-day calendar.
John H Linden and Victoria R. Bricker published their findings in Ancient Mesoamerica. They explain that while previous research has been working on something, they think it has to do with synodic periods — the time it takes for a planet to appear and then relative to the Sun, as seen from Earth, at the same point return in the sky - the key was to see it over a much longer period of time so that it was fully understood.
In other words, the Maya traced the 45-year pattern (20 periods of 819 days) of planetary alignment and turned it into a calendar. The confusing part of the 819-day period was the juxtaposition of the planets moving at vastly different speeds; but once he considers 20 cycles - that's 16,380 days, or about 45 years - the synodic periods of the planets they then knew match up exactly. As Popular Mechanics makes clear, Mercury's 117-day synodic period was always the first piece of the puzzle, but once the 20 periods are charted, each planet fits into the mix. “Mars can be a kicker for overall length. With a synodic period of 780 days, 21 periods equals exactly 16,380, or 20 cycles of 819,” notes Tim Newcomb. “Venus takes seven cycles to reach five 819-day counts, Saturn 13 cycles to reach six 819-day counts, and Jupiter 39 cycles to reach 19,819-day counts.”
Overall, this discovery is a testament to the advanced mathematics and careful astronomical observations of the Maya civilisation. "Rather than confining their attention to one planet," the authors added, "the Mayan astronomers who compiled the 819-day account presented it as a larger calendar system that could be used to predict the synodal periods of all visible planets , and as and points of comparison with their cycles in the Tzolkin and the Calendar Circle.