If you are reading this column, then we have survived the Maya Apocalypse of 2012. Or have we? It all depends on whether we have correctly correlated the Maya calendar with our own. What if we are off by a day or three? Or what if the apocalypse happened 260 years ago? What cruel irony to be certain that there was time to walk the dog, do laundry, or make New Year's resolutions, and then BAM! That's all, folks. The 2012 apocalypse phenomenon was created by the modern interpretation of the meaning of certain ancient Maya calendar cycles. But since there are no ancient Maya walking around still using the ancient calendar, the 2012 apocalypse predictions also depend upon how our calendar might be correlated to those last used in Mexico and Central America almost a thousand years ago.

As discussed in this column in July, the 2012 apocalypse predictions are linked to the ancient Maya calendar that modern scholars call the Long Count. We do not know what the Maya called it, very likely something like "the day count, " since it is at its most fundamental level a continuous tally of days stretching infinitely into both the past and the future. Here's a brief recap. The Long Count consists of time periods large and small, all based upon groups of single days. The lowest and most commonly used periods counted single days, months of 20 days, and years of 360 days. This calendar was unrelated to the solar year, hence the figure of 360 days, rather than 365 or 365.242 days, the true length of the so-called tropical year on Earth. Most ancient Maya dates, and there are hundreds, even thousands, use two additional larger time periods, which are units of 20 and 400 years (20 x 360 = 7,200 days, and 400 x 360 = 144,000 days). The ancient Maya used the Long Count to fix immovably in time events in the lives of the elite in cities such as Tikal, Copan, and Palenque: births, marriages, rituals, battles, and deaths. They never used the Long Count or their hieroglyphic writing to record commercial transactions or any details of life outside the palaces of the kings and nobles. The dates are unmovable and unrepeatable because the cycles are so long, just as the date Dec. 21, 2012 will never come again, unless someone in the remote future decides to reset our calendar.

Archaeologists believe that the earliest Maya lived about 500 B.C., and their civilization experienced 1,200 years of expansion, a time period comparable to the entire span of Republican and Imperial Rome. In the 8th century, Maya city-states began to fail. The collapse of what archaeologists call Classic Maya society was caused by a combination of drought, environmental degradation, and unsustainable populations. (For more detailed information on the topic, read David Webster's 2002 book *The Fall of the Ancient Maya* instead of, or at least before reading, Jared Diamond's 2005 *Collapse*.) There was a several-hundred-year renaissance in northern Yucatán, at Chichén Itzá, Uxmal, Mayapán, and elsewhere. But by the time the Spanish began invading Mexico in the early 16th century the Long Count was in disuse, probably because the elite culture with which it was so closely associated was so attenuated.

This thumbnail sketch of Maya history is to note that the entire span of pre-Columbian Maya culture falls within the roughly 5,000-year (5,126 to be exact) period that anchors the five lowest periods of the Long Count, beginning on a date in our calendar corresponding to Aug. 11, 3114 B.C. There were no Mayas in Mexico and Central America at this time, and archaeologists' best guess is that this date was selected because it was a mathematically predictable point of confluence between many cycles they were tracking, among them the periodicities of the moon and visible planets. But this was not the beginning of the Long Count, just the start of a significant cycle of human agency. That is, there are no human actors named as subjects of any of the many Maya texts that cast deep into the past and far into the future, only gods and the deified ancestors of the elite.

We write that anchor date of Aug. 11, 3114 B.C. as 13.0.0.0.0, which tells us that on this date 13 periods of 400 years were finished. To the right of the 13, the places for periods of 20 years, single years, months, and days are empty because they are already completed. The next day was 13.0.0.0.1, the next month 13.0.0.1.0, and the next year 13.0.1.0.0. When 400 years passed, the number in that place reset to zero. But Maya dates that have just these five time periods were an abbreviation of a much longer date, which we find written out on a few monuments, for example, Stela 1, from the site of Cobá, Mexico. There, instead of just giving us the five lowest time periods, 19 additional and higher periods are given. The 3114 B.C. date is thus expressed: 13.13.13.13.13.13.13.13.13.13.13.13.13.13.13.13.13.13.13.13.0.0.0.0, or 19 places with 13, and then the 13.0.0.0.0, or five lowest time periods which are most often given in Maya inscriptions. Each of these higher periods is a factor of 20 larger. After the Baktun, or period of 400 years, the fifth from the right here, we find counts of 8,000 years of 360 days (2,880,000 days), 160,000 years of 360 days (57,600,000 days), 3,200,000 years of 360 days (1,152,000,000 days), 64,000,000 years of 360 days (23,040,000,000 days), and so on. If we expanded this date to learn when the 24th period to the left began, it takes us 28 octillion years before the present (an octillion is 10 to the 27th power, or 1 followed by 27 zeros), and so far beyond the currently understood date for the Big Bang creation of our universe, 14 billion years ago, as to be incomprehensible, even if you have a computer. So whatever the ancient Maya thought happened in 3114 B.C., it was not the beginning of their calendar. On Dec. 21, 2012 the 13th period of 400 years since 3114 B.C. will end. But in a like manner, it is not the calendar's terminus. Several Maya dates are cast far into the future. One from Palenque looks forward to the next significant Long Count period ending, in A.D. 4772; another, from Quiriguá, Guatemala, discusses the actions of gods 400 million years hence. It seems straight out of H.G. Wells' *The Time Machine*.

In 1920, Santa Fe's part-time Maya archaeologist Sylvanus G. Morley wrote in his *Inscriptions at Copan* that all of Maya history could be completely understood if but one point of convergence between the Long Count and the Gregorian calendar could be discovered. To date scholars have advanced more than three dozen serious proposals to correlate the Maya Long Count with our calendar. The points of convergence Morley sought have been found in two places: the records made by the Maya and Spanish after the conquest of Yucatán in 1542, and in pre-Columbian references to astronomical phenomena, such as solar eclipses that we can check using modern eclipse tables. The reason the Maya calendar correlation remains unsettled today is because the data from early colonial sources is confusing, mainly because the Long Count was no longer used and had been replaced by an abbreviated count of 20-year periods. But the family of correlation constants that most scholars agree is correct all cluster a day or two before and after (mostly after) 584,283. As a preview for the tough going that follows, if this figure is correct, then the so-called Maya apocalypse will happen on Dec. 21. If the correlation constant is 584,285 — a figure preferred by many scholars — then it will be on Dec. 23. A correct correlation should agree with all of the solar eclipses the ancient Maya predicted or observed as well as with the phases of the moon they often recorded along with the Long Count dates. None of the proposed correlations agrees exactly with all of these data points.

The Franciscan friar Diego de Landa left Maya studies a critical document in his *Relación de las Cosas de Yucatán*, an account of his adopted country that he composed to defend himself from charges that he had illegally began his own inquisition in 1562 and had many Mayas interrogated, tortured and even killed for backsliding into paganism. Though clearly guilty (his superiors thought he had cracked), back in Spain, Landa was exonerated and was later named the first bishop of Yucatán. Landa used noble Yucatec Maya as informants, and they gave him much data about their history and culture. They told him that when the Spanish arrived in Yucatán, the calendar period called K'atun 11 Ajaw had just begun. In the several centuries preceding the Spanish conquest of Mexico, the Maya of Yucatán adopted what scholars call the Short Count, a cycle of 13 K'atuns, or periods of 20 Long Count years, or 7,200 days. Landa's source also noted that in 1553, the beginning of the Maya year (365-day calendar) occurred on July 16, or 12 K'an 1 Pop in the Maya calendars. Using the statement that K'atun 11 Ajaw had just begun in 1541, and that the date July 16, 1553, was 12 K'an 1 Pop, we can project back to a secure Long Count date of 11.16.0.0.0 13 Ajaw 7 Xul for a date in the year 1539. Calculating the interval between the days generates 11.16.13.16.3 as the Long Count for July 16, 1553. Scholars have turned to the Julian day count for the next step. Proposed in 1583 by the French astronomer Julius Scaliger, the Julian day count numbers every day from a fixed starting point: Jan. 1, 4713 B.C. It is useful to astronomers because, like the Long Count, it counts single days without any need to make reference to years, which are not composed of a whole number of days. The true length of the year, the so-called tropical year, is 365.242 days, hence the need for leap days every fourth year in our modern calendar. There is no need for fractions or leap years in the count of single days. The Julian Day Number (JDN) of July 16, 1553 is 2,288,488. If we subtract the total number of days in the second Long Count date above -- 11.16.13.16.3 is 1,704,203 days, or (11 x 144,000) + (16 x 7,200) + (13 x 360) + (16 x 20) + (3 x 1) -- we arrive at the correlation constant of 584,285 (2,288,488 - 1,704,203). This places the beginning of the current cycle of 400-year Long Count periods at 584,285 days after Jan 1, 4713 B.C., or Aug. 11, 3114 B.C.

This correlation's author, the great 20th-century archaeologist J. Eric S. Thompson, believed that for a variety of reasons the calendar recorded by Landa and other Spanish Colonial had slipped by two days. He later introduced arguments for a 584, 284 correlation and then a 584, 283 correlation. That latter correlation has become fixed in popular culture, and it produces the Dec. 21 doomsday date. However, many scholars prefer the original 584,285 figure, which places the Baktun ending on Dec. 23.

Using this constant to convert Maya dates to dates in our Gregorian calendar is complex, and we suggest using one of the many online programs or smartphone apps, but it can also be done with a calculator or with pencil and paper, as Morley would have done it. Here's how. This explanation follows that presented in *The Ancient Maya* by Robert Sharer and Loa Traxler — the sixth edition of the book Morley originally wrote in 1946, which has been revised so much that the Santa Fean's name is no longer on the title page. You first find the total number of days in a Long Count date. For example, 9.15.6.14.6 multiplies out to 1,406,446 days. We add this figure to the correlation constant to arrive at the corresponding Julian Day Number — 1,990,729 = 1,406,446 + 584,283. Referring to the chart attached to this article, next subtract the nearest smaller Julian Day Number — 1,976,730, found on the line corresponding to the year 700 in the modern Gregorian calendar. 1,990,729 - 1,976,730 = 13,999 days, or 38 years and 129 days. The Long Count date 9.15.6.14.6 thus corresponds to the year 738 in our calendar. To calculate the exact date we must subtract the number of leap days our Gregorian calendar adds every fourth year of those 38 years (the Julian Day Numbers do not use leap days). Subtracting the nine leap days in 38 years yields 120, and the 120th day of the year is May 1. Finally we arrive at the correlated date: 9.15.6.14.6 is May 1, 738. Converting Gregorian calendar dates to Maya Long Count reverses the process, though it is somewhat more complicated.

So are we still doomed? No matter what correlation we wish to use to connect our calendar to the ancient Maya Long Count, most of us will probably live to see 2013. Whew! If the ancient Maya were here they would likely record that they celebrated the end of the 13th Baktun, amid much hoopla, on Dec. 21, 2012. Then they would very likely connect this event to the next great period, ending on Oct. 21, 4772. ◀

**For further reading**

*Exploring the 584,286 Correlation between the Maya and European Calendars* by Simon Martin and Joel Skidmore, Precolumbian Art Research Institute Journal 13, No. 2 (2012). Available online; see www.mesoweb.com/pari/publications/journal/1302/Correlation.pdf

*Maya Hieroglyphic Writing* by J. Eric S. Thompson, University of Oklahoma Press

*The Decipherment of Maya Script* by David Kelley, University of Texas Press

*Skywatchers of Ancient Mexico* by Anthony Aveni, University of Texas Press