Background
The forgotten calendar
Museum Volkenkunde has opened an exhibition on the Mayans, their calendar and the end of the world. Spoiler alert: you can visit the exhibition after 21 December too.
Bart Braun
Wednesday 28 November 2012

Three events have been scheduled for the 21st of December: one is bound to happen, one is uncertain and the third is extremely unlikely. Although you can't completely rule out the possibility that the world will end that day, for now there is no reason to suppose it will. Even the Pope, the head of an international organisation that preaches about the end of the world, does not believe this prophecy. At least, nothing has been heard from the mythical planet of Nibiru and the sun shows no signs of exploding.

However, the sun will have a special position in the sky on the 21th – at least, special for astronomers. Lesser mortals who peruse the skies will not notice much out of the ordinary. But if the sun were to radiate very little light, and the town of Leiden were to produce less light pollution, you would be able to see the Milky Way and see that the sun is positioned in the centre of the Milky Way. It is frequently at the centre of the Milky Way, but it very rarely happens precisely at the solstice. It should be noted that the apparent width of the Milky Way depends, of course, on how well you are looking. In fact, on the 18th of December, it is slightly more to the centre.

But we also have the Mayan Calendar, which is supposedly to end. This theory is surrounded by a whole fog of misunderstandings and obscurity. At least, no one has ever discovered a note saying: "Dear world, our calendar will end on the 21st of December 2012 and the earth will implode", even if it is simply because the Mayans never recorded time like that. There is one stone, the Tortuguero Monument 6, with a scarcely legible inscription that refers to the final date of the Mayan Calendars, the Long Count.

In Leiden, Museum Volkenkunde has a website with an example of calendar dating according to that system: 9.18.12.14.17. The last figure shows the number of days, the figure before that represents the number of winals (periods of 20 days); there are 12 Tuns to every eighteen winals; twenty Tuns form a K'atun of which eighteen have passed by this date, and then there are another twenty K'atuns in a Bak'tun. Those of you who are quick at arithmetic will notice that a Bak'tun has 144,000 days. If you want to know more about this, you can attend the workshop on Mayan calendar calculation at the museum on Sunday. For now, we need to know two things:

If you multiply all those time periods with the number of days they represent, you get a total of number of days, which is, in this case 1,430,217. That is the number of days since the "year nought", the beginning of creation according to the Mayans. We will come back to this in a minute.

The second interesting thing is that there are only thirteen of these Bak'tuns. When we reach the end of the thirteenth Bak'tun, the year count that-doesn't-work-with-years is full.

"This calendar was completely lost in obscurity until Western scientists deciphered it," explains anthropologist Ruud van Akkeren. "Modern Mayans in Guatemala asked me what happens when it ends. 'According to the rest of the world, you should tell us,' I told them. Literally, nothing has been written about what is supposed to happen. All we have is the Tortuguero stone, which presents that date, and says that the god Bolon Yokte K'uh will be present. We can relate that to all sorts of myths; he is the god of many things, including calendar transitions. Many of the ancient Mayan legends tell of heroes who die and come to life again. The god of maize dies and returns as a maize shoot; the sun god dies and returns as the sun. At the end of a cycle, something new is born."

This theme can be observed in the Mayan year count; after all, you don't expect your car to explode when odometer turns right round and in the same way, the Classic Mayans did not expect the world to end. At least, they have predicted events at times that are

much further in the future.

Now, let's get back to the dating system. These five figures determine which day it is according to the Mayan year count. How do you calculate a date like that to fit a date in our Gregorian calendar? That is not very straightforward, because the Mayan's Long Count was out of use when the Spanish arrived. At the beginning of the last century, archaeologist Eric Thomson reached the conclusion that the Mayan year count started on the 13th of August in our year 3114 B.C, so the count should end on 21-12-2012.

However, Thomson's conclusion has been under attack in recent years. For instance, there is a tablet that links the positions of the planet Venus to certain dates, and Thomson's dates do not match the position of Venus on those days. If you look for dates that match the position of Venus, the calendar has to be shifted up about 200 years. There is more archaeological evidence that points in the same direction: the calendar ends in December 2220. So we'll have to wait a while before we meet the god of calendar transition.

Exhibition: 21 December 2012: The end of the world. Open until 23 May 2013, or until the end of the world, depending on which comes first. Museum Volkenkunde, Steenstraat 1, Leiden.