Current technology may provide the power to decipher the behavior of objects inhabiting the cosmic void, but millennia ago astronomical wisdom was already present in cultures such as the Maya, who monitored the skies and based their complex architecture on the movements of the stars. Until a few years ago, it was known that there was a very close relationship between the Maya calendar and planetary cycles, but it was not known how accurate it was until a new research found the key element to understanding Maya astronomy.

## The Maya Calendar is Simply Perfect

It has taken modern societies centuries to understand that ancient Mayan knowledge is much deeper than a simple series of pre-Hispanic codices. The wisdom of Mesoamerican culture exceeds expectations, for despite not having current technology, they were able to decipher the synodic periods of planets and even incorporate these periods into their intricate Mayan calendar, as revealed by research published in the scientific journal *Ancient Mesoamerica*.

## Maya Calendar

Unlike our relatively simple calendar of 365 days divided into 12 months, the Maya calendar made use of different intertwined cycles. The most well-known are the Tzolk’in, which lasted 260 days, while the Haab lasted the same as the current calendar of 365 days. These two cycles synchronized every 52 years, giving rise to another period called the Calendar Round.

In addition to these interrelated cycles, inscriptions found in various Maya archaeological sites speak of a period of 819 days. The texts reveal that each date in this cycle is associated with one of the four cardinal points, meaning that 4 are required to complete the four cardinal points. But knowing the intricacy of Maya wisdom, researchers have long suspected that their calendar would be closely related to astronomy and the movement of planets, and it seems they were not wrong.

## The mysterious Cycle of 819 Days

The synodic periods of planets refer to the time it takes each planet in the Solar System to return to the same position in the celestial map, as seen from Earth’s perspective. The synodic period is different for each planet, as their orbits are very different, but the Maya found the pattern between them and incorporated it into their calendar.

## Maya Calendar

For example, Mercury has a synodic period of 117 days that fits perfectly with the Maya cycle of 819 days when multiplied by seven. Researchers were not sure if the other synodic periods fit perfectly with 819, but then they discovered that 20 rounds of 819 days, equals a total of 16,380 years (approximately 45 years), which is perfectly divisible by the synodic periods of each planet.

Saturn takes 378 days to return to its same position in the sky, if 13 of its cycles are taken, a total of 4,914 days is obtained, which is exactly six times 819. Venus, on the other hand, has a synodic period of 584 days that multiplied by five equals a Haab. Jupiter takes 399 days to return to its position in the sky, 39 repetitions of its synodic cycle coincide perfectly with 19 cycles of 819 days.

## Planetary Alignment in March

Finally, Mars’ synodic period is 780 days which multiplied by 21 gives a total of 16,380 days, the same amount that is obtained by repeating the mysterious Mayan cycle of 819 days twenty times.

In addition to the finesse of the synodic periods, it is worth noting that 16,380 is also a multiple of 260, which means it coincides with the Maya period known as the Tzolk’in.

Mayan mathematics and astronomy are so precise that it simply seems we are talking about something

*Story originally written in Spanish by Alejandra Martínez in Ecoosfera.*