Posted by: Johan Normark | October 9, 2010

2012: The Long Count may be off by at least 60 days

Nine years ago I read an interesting article by Gerardo Aldana (who now is associate professor at the University of California at Santa Barbara). I have mentioned it in the passing at least twice on this blog. Back then he claimed that the correlation issue between the Maya Long Count and the Julian and Gregorian calendars has not been resolved. He based his arguments Maya astronomical practices. Most Mayanists use the so-called GMT-correlation constant that sets the 13 Baktun date at December 21, 2012 (the sole reason for all the 2012 nonsense). Other Mayanists, such as Schele and Freidel, favor a correlation that is two days later.

GMT stands for the Mayanists Goodman, Martinez, and Thompson who all contributed to the establishment of the constant. Goodman and Martinez relied largely on Calendar Round dates they found in Colonial documents that could be tied to Gregorian dates.

It appears that Aldana’s paper had little impact on the Mayanist (and 2012) community as they continue to use the GMT-correlation. For the 2012ers this continuation is a must since their whole business relies on this correlation (since it so nicely coincides with the Winter Solstice). Aldana argues that the GMT is wrong and it partly has to do with the Colonial impact (again I must stress the importance of the Colonial period changes which many Mayanists do not tackle). In his conclusions Aldana wrote that:

the GMT is not 2 or 3 days off, nor even 20, but at least 60 days. I emphasize “at least” for two reasons. First, the most important assumption behind the GMT is that of continuity. Scholars have been willing to accept the criticisms of the GMT since the result is a continual Calendar Round count between ancient and colonial times. Yet this continuity requires that we sacrifice the understanding that comes along with the ability to read the hieroglyphic script—namely, the inscriptions of the Solar Stelae at Copán, the architecture of Waxaktun, and the inscriptions of Chich’en Itza. Now, to accept the GMT is to accept that Balaj Chan K’awiil [ruler of Dos Pilas] very well could have set his battle date by the appearance of Chak Ek’ [used to be believed to be Venus but in another study Aldana believes it is a meteorite], but the Early Classic rulers of Waxaktun, Copán Ruler 12, and the Terminal Classic kings of Chich’en Itza were all off on their solar calendar by 60 days! Second, simply pushing the correlation forward by 60 days would right the solar issue, but would violate most of the other associations that have been used to support the GMT.

Without continuity, the GMT loses its weight of argument and allows us to contemplate anew the criticisms that have been leveled against its acceptance in recent times. In particular, scholars of the Postclassic have noted that the GMT creates an ugly gap in the archaeological record. Accepting these criticisms might revise the dating of Maya culture in the Christian calendar by up to 260 years [a 13 Katun cycle]. This paper has not set out, however, to provide an alternative to the GMT correlation. Indeed, one cannot hope for an unseating of the GMT without treatment of the radiocarbon data that support it. While Arlen Chase has argued well that radiocarbon data alone are not sufficient to provide a calendar correlation, the weight that they bear is too great to be displaced by epigraphic and astronomically-based argumentation alone.” (Aldana 2001:16)

Aldana is publishing these ideas (and new information as well I assume) in an article in a new anthology called  Calendars and Years II: Astronomy and Time in the Ancient and Medieval World (ed. John Steele). I have not read it yet but according to this blog, he focuses on the work of Floyd Lounsbury who used the Venus Table in the Dresden Codex to establish the correlation between specific dates and the movements of Venus. Followers of Lounsbury’s work concluded that the GMT constant was correct. However, Aldana suggests that Lounsbury’s conclusions are far from irrefutable. Corroborating data is even less reliable.

Aldana does not come up with an alternative correlation constant (and I wonder myself if all Maya sites really had the same base date in the Gregorian calendar). However, the correlation issue is known to Mayanists but apparently not very well known to 2012ers. Hence, Jenkins’ whole cosmology behind the Galactic Alignment on December 21, 2012, falls to pieces as do much of the 2012 nonsense if Aldana is correct.



  1. The Venus Cycle Could Be An Important Factor For The Long Count,It Could Be Correlated When Venus First Apears As The Evening Star Should Be An Oc/Dog Day

  2. Apart from that I doubt that there ever was ONE Long Count I am not that concerned with how much the calendar is off since the archaeological dating methods have a much lower resolution. Of course some studies are dependent on exactly what time of the solar year a Long Count event took place, such as warfare. It is usually believed that most battles took place in the agricultural off-season. Changing the correlations two months will change these interpretations.

  3. The Short Count Was Also Used Measuring Katuns 20yrs in A Cycle Of 2561/4 yrs,There Is Some Conflict In Which Short Cycle Events May Have Happened.

  4. The short count, or the may cycle of 13 katuns, has been revived by Prudence Rice as an explanation for Classic period sociopolitical organization. I am far from convinced that her model, based on Colonial documents describing Postclassic period events is relevant for the Classic and Late Formative periods.

  5. Hence, Jenkins’ whole cosmology behind the Galactic Alignment on December 21, 2012, falls to pieces as do much of the 2012 nonsense if Aldana is correct.

    When their doomsday fails to materialize, they will pretend to use Aldana’s work to conduct a new psuedo-analysis of the Mayan calendar, and from that forecast a “correct” doomsday. Perhaps it will fall on February 19th, 2013.

  6. Jenkins is not proposing a doomsday but others use his ideas. Yes, they will make up a new doomsday when this one fails.

  7. […] blogger and my internet acquaintance Johan Normark writes more on this issue in his post, “2012: The Long Count may be off by at least 60 days,” and I highly recommend reading it as he actually studies the […]

  8. […] next academic challenge of note is by Geraldo Aldana who says that the end date may be off by as much as 60 days. We can dismiss Carl Calleman’s […]

    • If there will be a big , Planet wide calamity in Dec 21, 2012 I think it will be like as John Wyndham wrote in his book in 1951; The Day Of The Triffids.
      And in My opinion Dec 21 2012 Will be the Day Of The Triffids.

  9. […] 2012 prediction because they now believe that the calendar might be wrong by at least 60 years. [2] Researchers now claim that they cannot be sure if the Mayans were tracking a meteor or Venus and […]

  10. December will be doomsday

    • Yes,

      and Chstmas will be in december…

      nandy, living on earth, (astronomical)


%d bloggers like this: