00:00Back in December 2012, a lot of people were freaking out over the idea that the world
00:05might end in some catastrophic event.
00:08And it was all thanks to the famous Maya calendar.
00:11This ancient way of tracking time had been the subject of endless speculation.
00:16But one of its biggest mysteries was definitely an 819-day count found in some versions of
00:23the calendar.
00:24No one could explain why it was there or how it worked, until recently, when a group of
00:29researchers from Cambridge might have finally cracked the code.
00:34First things first, how does the Maya calendar work?
00:38So the system the Maya civilization used to track days was based on something we now call
00:44the calendar round.
00:46Think of it like three interlocking gears.
00:49These are three cycles working together.
00:52The first is a 365-day solar year, known as Hab.
00:58The second is a cycle of 20 names.
01:01And the third is a cycle of 13 numbers, which forms a 260-day sacred calendar, called Tzolk'in.
01:12Just like we'd say something like December 25th, 2025, they named their days based on
01:18how these three cycles lined up.
01:21For example, here we have the day 3 Manic and the 14th of the month Hab.
01:28It takes 52 years for the three cycles to align in the same way again.
01:33After that, the days start repeating.
01:37But this is where things start to get more complicated and mysterious.
01:42On some Mayan monuments, we have also found enigmatic inscriptions pointing to the existence
01:48of another cycle, the 819-day count.
01:53There are about 20 examples of these inscriptions mostly found in places like Palenque and Yaxchilan
01:59in Mexico.
02:00So it didn't seem random at all, and this calendar must have been hiding a big secret.
02:07Early research showed that the 819-day cycle was represented by one of four colors and
02:13the cardinal directions associated with them.
02:17Dark was tied to the west, red to the east, white to the north, and yellow to the south.
02:24Researchers also discovered that this period of time could be broken down into three smaller
02:28cycles.
02:30One of 9 days, one of 7 days, and one of 13 days.
02:35Multiply them together, and you'd get 819 days.
02:39Pretty cool, but why did they do that?
02:43This color scheme and the three cycles seemed like a basic level of interpretation, and
02:48experts were pretty sure its real purpose was still hidden from us.
02:54Another thing researchers noticed is that this strange count of days was mostly shown
02:59using a wide glyph, followed by a number.
03:03But in some cases, they also added a glyph representing Kawil.
03:09This was a powerful Maya deity, often associated with creation and lightning.
03:15He was usually symbolized by a torch coming out of his forehead, representing the spark
03:20of light.
03:21But in the 90s, a study suggested that when Kawil's inscription showed smoke and fire
03:26coming from his forehead, it could actually represent the planets Jupiter or Saturn, or
03:31maybe even both.
03:34Wait, that means that the 819 days count could be linked to both planets in some way.
03:41From there, research focused on figuring out what that link might be.
03:47The first conclusion is that this calendar might have helped the Maya track the movements
03:51of those planets in some way.
03:54Then they started noticing something interesting.
03:57These cycles could be specifically tied to the synodic periods of Jupiter and Saturn.
04:03By synodic periods, we mean the time it takes for a celestial body, like a planet, to return
04:08to the same or nearly the same position as seen from Earth.
04:14While this possibility was pretty exciting, something didn't quite add up.
04:20Each planet moves very differently, and trying to fit multiple planets into an 819-day span
04:26just didn't seem to work.
04:28In other words, this four-part color-coded calendar system was simply too short to align
04:34perfectly with the synodic periods of the visible planets.
04:39So it looks like we're back to square one.
04:42This mystery had people scratching their heads for ages, until 2023, when specialists realized
04:48they might have been looking at it all wrong.
04:52Researchers actually needed to shift their perspective.
04:55Instead of seeing this system as 819 days, they needed to consider the number as representing
05:01timelines, and this period of time could be just a small part of a much, much bigger calendar.
05:10You see, as we said earlier, this cycle seemed to track the period when a planet became visible
05:15to people on Earth.
05:17To prove that these 819 cycles were timelines, not actual days, researchers needed a planet
05:24that could serve as a starting point to back up their theory.
05:29In this case, it was Mercury.
05:31And there's a pretty simple reason for that.
05:33Mercury's synodic period is 117 days, which fits perfectly into the calendar count.
05:39I mean, if you take 1819 and divide by 117, you get the number 7.
05:47So Mercury is the only visible planet whose synodic cycle fits neatly into this period
05:53as whole numbers.
05:55Perfect.
05:56Now they had a solid starting point.
05:59From there, they needed to expand the calendar by increasing its length to 20 periods of
06:04819 days.
06:06Suddenly, a pattern emerges.
06:09And just like that, all the synodic cycles of the planets fit perfectly into the system.
06:16For example, Saturn's synodic period from 378 days lines up perfectly after 6 819-day
06:25cycles, Venus aligns every 5 cycles, Jupiter every 19 cycles, and Mars, which takes the
06:33longest, needs 20 cycles.
06:36In other words, it takes about 45 years for Mars to align with the synodic periods of
06:41all visible planets.
06:45So this is how researchers determined that the ancient civilization wasn't referring
06:49to days, but rather to timelines.
06:52The Maya astronomers came up with this count as part of a larger calendar system of 20
06:58periods.
06:59But then a question comes up.
07:01Why was studying the synodic period so important to the Maya?
07:05Well, we don't have super specific answers about this mysterious calendar yet.
07:11But what we can say for sure is that the Maya truly believed in the powerful influence
07:16of the cosmos on daily life.
07:18So maybe they wanted to analyze how the movements of all the visible planets lined up with their
07:24other calendars.
07:27Of course, this system is just one part of the Maya's amazing and advanced understanding
07:32of astrology.
07:34And it wasn't just about using astrological cycles for planting and harvesting.
07:39They also had crazy specific knowledge, like how to predict solar eclipses.
07:47Archaeologists believe the Maya connection to the stars is reflected in the ruins of
07:50their world.
07:52Take the famous pyramid in the ancient city of Chichen Itza, located in Mexico's Yucatan
07:57Peninsula.
07:59If you look closely at the base of its staircase, you will see a snake's head carved in stone.
08:05But here's the coolest part.
08:07During the spring and fall equinoxes, when day and night are exactly the same length,
08:12the sun casts sharp triangular shadows on the staircase.
08:16It creates the illusion of a snake slithering down the steps.
08:22Another example of how they used their knowledge of astronomy in their temples is in Tikal,
08:27Guatemala.
08:28Built around year one of the Common Era, this pyramid is considered one of the Maya's earliest
08:34astronomical complexes.
08:36And its alignment and orientation allowed them to track and calculate solstices and
08:41equinoxes with incredible precision.
08:46The Maya were skilled sky watchers.
08:48Just like we have modern-day high-tech observatories with round domes, they had something similar.
08:55Meet El Caracol.
08:56The name means snail in Spanish and refers to the spiral staircase inside the tower.
09:03Built around 906 Common Era, it was the perfect place to observe all the changes in the sky
09:09and track the movements of the sun, moon, planets, and stars.
09:14Unlike us today with our telescopes, satellites, and advanced tools, the Maya relied entirely
09:20on naked-eye observation.
09:22And that makes their achievements even more incredible.
09:29That's it for today.
09:30Hey, if you pacified your curiosity, then give the video a like and share it with your
09:34friends.
09:35Or if you want more, just click on these videos and stay on the Bright Side!
Comments