The smallest unit in Maya timekeeping is the day (k’in - sun, day). Hence, all the 2012 related claims on how accurate the Maya calendar(s) were seem to skip that very important notion. The reason why the Maya appears to have had accurate calendars is that they counted celestial cycles, such as in the Venus table in the Dresden Codex, for a long time. The Maya only used integers, never fractals. The fractals that appear in Mayanist literature are simply the result of a division of long periods divided by the known number of cycles. The likelihood that they were able to pinpoint the exact hour or minute when the winter solstice occur in 2012 is nonexistent (even if we believe the 13 Baktun date falls on that date). The winter solstice in 2012 occurs on December 21, at 11:12 AM GMT, which equals 5:12 AM in the Maya area. This is about one hour before sunrise so it is of some importance to understand when that smallest temporal unit began.
There appears to have been various ways to calculate when the day began. Did it last from sunset to sunset, sunrise to sunrise, noon to noon or midnight to midnight, or something else? It depends on what calendar you talk about. Peter Mathews has argued that several Late Classic inscriptions, such as Stela 18 at Yaxchilan and Stela 8 at Dos Pilas, indicate that the tzolkin began before midnight and was followed by the haab day at sunrise. David Stuart reports that on a door lintel, now at Hecelchakan in Campeche, the new tzolkin day enters a preceding haab day. Hence, in an inscription where we have a Calendar Round date (tzolkin and haab), the days in the various cycles did not begin at the same time.
Alexandre Tokovinine has located other dates that do not correspond to this the haab-tzolkin correlation system above. These include the ninth baktun ending on Copan Stela 63 and the Motmot marker in AD 435 (GMT correlation). On these monuments the haab date is one station ahead of the so-called Calendar Style 1 system. The 22.214.171.124.0. Calendar Round dates are 8 Ajaw 14 Keh instead of 8 Ajaw 13 Keh. Such discrepancies have earlier been believed to be scribal errors. However, on a painted inscription found at La Sufricaya in Peten, the arrival of Sihyaj K’ahk’ to Tikal is recorded to have occurred on 11 Eb 16 Mahk. The same event is recorded on Tikal Stela 31 and elsewhere and there the Calendar Round dates are tied to the Long Count and there the date is 11 Eb 15 Mahk. Similar discrepancies are found on Copan Altar Q and on the sarcophagus lid in the Temple of the Inscriptions at Palenque. It is the haab days that differ in these cases. It seems that the new haab day began before midnight, probably at noon or sunset. In contrast to Mathews’ system, when the tzolkin is roughly a quarter of a day or more ahead of the haab, we have here a system where the haab is ahead of the tzolkin.
The Calendar Round day is shorter than the tzolkin and haab day respectively (but it is not a clearly defined temporal unit due to seasonal changes in sunrise and sunset). The Calendar Round days are separated by periods of transition. In Mathews’s system a Calendar Round day begins at sunrise and ends at midnight, but in the other system the Calendar Round day begins at midnight and ends at sunset. Since the Long Count is a count of tzolkin days this latter Calendar Round system is found in inscriptions without the Long Count attached to it.
Although I am not a fan of ethnographic analogies it is of interest that some contemporary highland Maya communities count their days from sunset to sunset. Other Maya groups count their days from sunrise to sunrise. There is also a reversal of sun-related directional terms in the highland. Among the contemporary Mam west is called elni and east okni. In Classic Ch’olti’an, the language of the Classic period lowland inscriptions, west is called ochk’in and east is called elk’in (later lak’in). Tokovinine argues that the “directional terms mirror different conceptualizations of the sun’s movement in terms of where it ‘ends’ and ‘begins’” (p 19).
Tokovinine notes that the unusual dates discussed above deals with or are commissioned by people connected to Teotihuacan. Sihyaj K’ahk’ is believed to have been a warlord sent out by the Teotihuacano ruler Spearthrower Owl in the late fourth century AD. Copan also has connections to Teotihuacan. It is possible that Teotihuacan had a distinct way of counting its versions of tzolkin and haab and that this is reflected in the inscriptions discussed above. It could also reflect Classic Maya ideas about Teotihuacan. In Classic Maya narratives Teotihuacan is located in the west. Tokovinine speculates “that the Maya saw Teotihuacan far in the west as a place where days were nights and consequently where the haab was counted by night suns, from sunset to sunset” (p 20).
Why is this discussion relevant to the whole 2012 circus? It is because Jenkins, for example, argues that the whole Long Count was designed to end on the winter solstice sunrise in 2012. Jenkins usually leave out the haab date and he focus on the tzolkin date. This has mainly to do with the fact that he wishes to correlate the beginning of the Long Count with its supposed end (which both falls on 4 Ajaw). However, the haab dates are different at the beginning and at the end. Even though the Long Count follows the tzolkin days, the haab cannot be ignored (the Maya didn’t). According to Mathews, then, the sunrise is associated with haab, not tzolkin. Only together with the haab, as the Calendar Round date, do the day begin at sunrise. But then the whole idea of Long Count cycles is not as neat since the different haab dates disturbs the symmetry the 2012ers desire.
Further, since highland communities today count the day from sunset to sunset and Jenkins’ whole argument is based on Izapa (also in the highland), his assumption that the Izapans focused on sunrise is questionable. Of course, the highland focus on sunset may reflect later Teotihuacan influences so it may not have existed when the Long Count was initiated. However we see it, we cannot be sure that there was a homogenous view of defining the beginning and end of the day throughout the Maya area even before the Teotihuacano entrada.
Tokovinine, Alexandre (2010). The western sun: an unusual tzolk’in-haab correlation in Classic Maya inscriptions. The PARI Journal 11(2):17-21.