A sketch of stela C from Quirigua, which gives the date of creation as 13.0.0.0.0

By now, you’ve probably heard that on December 21, 2012, just two weeks from today, the ancient Mayan calendar will run out, and the world will end! This is approximately as silly as thinking the world will end on December 31 because your wall calendar runs out on that day.

How did this get started? Well, the Mayan civilization of what is now southern Mexico were some of the best astronomers who ever lived before the invention of the telescope. They measured the motions of the planets to great precision and constructed a very accurate and complex calendar system. To express dates over very long periods, they created the Long Count, which can list dates over a span of thousands of years as a string of five numbers.

In the Long Count, the unit 0.0.0.0.1 is 1 day. 0.0.0.1.0 is 20 days. 0.0.1.0.0 is 360 days, or 1 year on the Mayan calendar, even though this doesn’t quite line up with the Sun. Then, 0.1.0.0.0 is 20 years, and 1.0.0.0.0 is 400 years (394 years on our calendar). This unit is called a b’ak’tun.

According to inscriptions translated by archeologists, the Mayans believed the world was created on August 11, 3114 BC, a date that they rendered as 13.0.0.0.0 (sort of like how we start our day at 12:00 midnight in the United States instead of 0:00), The end of this first b’ak’tun was written as 13.19.19.17.19, which was followed by 1.0.0.0.0.

It turns out that on December 20, 2012, the Long Count gets back up to 12.19.19.17.19, the end of the 13th b’ak’tun, which will roll over to 13.0.0.0.0 on December 21. One Mayan text says that the current world is the fourth world, after three earlier worlds were created and destroyed by the Mayan gods. Since the most recent world ended on 12.19.19.17.19, we might be in trouble come December 21, right?

Wrong! Even if you happen to follow the Mayan religion (some people in Central America still practice a Catholicized version of it), the Mayans themselves didn’t believe the world would end with the 13th b’ak’tun. None of the inscriptions make any kind of unambiguous prophecies for that date. In fact, they didn’t even plan to roll over from 13.19.19.17.19 back to 1.0.0.0.0 again, something that would have happened on March 26, 2407. Instead, the calender will just keep going to 14.0.0.0.0, and one inscription extrapolates all the way to October 13, 4772, when 19.19.19.17.19 rolls over to 1.0.0.0.0.0. That’s right, they were ready to add a sixth number to the Long Count.

And that’s far from the most distant gave computed by the Mayans. Another inscription gives an alternate date of creation of 13.13.13.13.13.13.13.13.13.13.13.13.13.13.13.13.13.13.13.13.0.0.0.0! If the world still started on August 11, 3114 BC, we won’t cycle back around to that same date until January 28, 26,871,657,487,833,425,737,694,814,070. (That’s 2.687*10^28 years from now if you don’t feel like counting all those digits.)

One part of the Mayan story is true, though. The Mayans did believe that reaching the date of 13.0.0.0.0 was an important event: specifically, a meaningful anniversary and a cause for celebration. So take a page out of these people’s book, and have some fun with it. And don’t panic: it’s not the end of the world.

In my next post, I’ll explain why some of the particular theories of impending doom are just as absurd as putting stock in the Mayan Calendar.