Maya calendar

The Maya calendar is a system of distinct calendars and almanacs used by the Maya civilization of pre-Columbian Mesoamerica, and by some modern Maya communities in highland Guatemala.

These calendars can be synchronized and interlocked, their combinations giving rise to further, more extensive cycles. The essentials of the Maya calendric system are based upon a system which had been in common use throughout the region, dating back to at least the 6th century BC. It shares many aspects with calendars employed by other earlier Mesoamerican civilizations, such as the Zapotec and Olmec, and contemporary or later ones such as the Mixtec and Aztec calendars. Although the Mesoamerican calendar did not originate with the Maya, their subsequent extensions and refinements of it were the most sophisticated. Along with those of the Aztecs, the Maya calendars are the best-documented and most completely understood.

By the Maya mythological tradition, as documented in Colonial Yucatec accounts and reconstructed from Late Classic and Postclassic inscriptions, the deity Itzamna is frequently credited with bringing the knowledge of the calendar system to the ancestral Maya, along with writing in general and other foundational aspects of Maya culture.

General overview

The most important of these calendars is one with a period of 260 days. This 260-day calendar was prevalent across all Mesoamerican societies, and is of great antiquity (almost certainly the oldest of the calendars). It is still used in some regions of Oaxaca, and by the Maya communities of the Guatemalan highlands. The Maya version is commonly known to scholars as the Tzolkin, or Tzolk'in in the revised orthography of the Academia de las Lenguas Mayas de Guatemala. The Tzolk'in is combined with another 365-day calendar (known as the Haab, or Haab' ), to form a synchronized cycle lasting for 52 Haabs, called the Calendar Round. Smaller cycles of 13 days (the trecena) and 20 days (the veintena) were important components of the Tzolk'in and Haab' cycles, respectively.

A different form of calendar was used to track longer periods of time, and for the inscription of calendar dates (i.e., identifying when one event occurred in relation to others). This form, known as the Long Count, is based upon the number of elapsed days since a mythological starting-point. According to the correlation between the Long Count and Western calendars accepted by the great majority of Maya researchers (known as the GMT correlation), this starting-point is equivalent to August 11, 3114 BC in the proleptic Gregorian calendar or 6 September in the Julian calendar (−3113 astronomical). The Goodman-Martinez-Thompson correlation was chosen by Thompson in 1935 based on earlier correlations by Joseph Goodman in 1905 (August 11), Juan Martínez Hernández in 1926 (August 12), and John Eric Sydney Thompson in 1927 (August 13). By its linear nature, the Long Count was capable of being extended to refer to any date far into the future (or past). This calendar involved the use of a positional notation system, in which each position signified an increasing multiple of the number of days. The Maya numeral system was essentially vigesimal (i.e., base-20), and each unit of a given position represented 20 times the unit of the position which preceded it. An important exception was made for the second-order place value, which instead represented 18 × 20, or 360 days, more closely approximating the solar year than would 20 × 20 = 400 days. It should be noted however that the cycles of the Long Count are independent of the solar year.

Many Maya Long Count inscriptions are supplemented by a Lunar Series, which provides information on the lunar phase and position of the Moon in a half-yearly cycle of lunations.

A 584-day Venus cycle was also maintained, which tracked the heliacal risings of Venus as the morning and evening stars. Many events in this cycle were seen as being astrologically inauspicious and baleful, and occasionally warfare was astrologically timed to coincide with stages in this cycle.

Other, less-prevalent or poorly-understood cycles, combinations and calendar progressions were also tracked. An 819-day count is attested in a few inscriptions; repeating sets of 9- and 13-day intervals associated with different groups of deities, animals and other significant concepts are also known.

Maya concepts of time

With the development of the place-notational Long Count calendar (believed to have been inherited from other Mesoamerican cultures), the Maya had an elegant system with which events could be recorded in a linear relationship to one another, and also with respect to the calendar ("linear time") itself. In theory, this system could readily be extended to delineate any length of time desired, by simply adding to the number of higher-order place markers used (and thereby generating an ever-increasing sequence of day-multiples, each day in the sequence uniquely identified by its Long Count number). In practice, most Maya Long Count inscriptions confine themselves to noting only the first 5 coefficients in this system (a b'ak'tun-count), since this was more than adequate to express any historical or current date (with an equivalent span of approximately 5125 solar years). Even so, example inscriptions exist which noted or implied lengthier sequences, indicating that the Maya well understood a linear (past-present-future) conception of time.

However, and in common with other Mesoamerican societies, the repetition of the various calendric cycles, the natural cycles of observable phenomena, and the recurrence and renewal of death-rebirth imagery in their mythological traditions were important and pervasive influences upon Maya societies. This conceptual view, in which the "cyclical nature" of time is highlighted, was a pre-eminent one, and many rituals were concerned with the completion and re-occurrences of various cycles. As the particular calendaric configurations were once again repeated, so too were the "supernatural" influences with which they were associated. Thus it was held that particular calendar configurations had a specific "character" to them, which would influence events on days exhibiting that configuration. Divinations could then be made from the auguries associated with a certain configuration, since events taking place on some future date would be subject to the same influences as its corresponding previous cycle dates. Events and ceremonies would be timed to coincide with auspicious dates, and avoid inauspicious ones.

The completion of significant calendar cycles ("period endings"), such as a k'atun-cycle, were often marked by the erection and dedication of specific monuments (mostly stela inscriptions, but sometimes twin-pyramid complexes such as those in Tikal and Yaxha), commemorating the completion, accompanied by dedicatory ceremonies.

A cyclical interpretation is also noted in Maya creation accounts, in which the present world and the humans in it were preceded by other worlds (one to five others, depending on the tradition) which were fashioned in various forms by the gods, but subsequently destroyed. The present world also had a tenuous existence, requiring the supplication and offerings of periodic sacrifice to maintain the balance of continuing existence. Similar themes are found in the creation accounts of other Mesoamerican societies.

Tzolk'in

Main article: Tzolk'in

The tzolk'in (in modern Maya orthography; also commonly written tzolkin) is the name commonly employed by Mayanist researchers for the Maya Sacred Round or 260-day calendar. The word tzolk'in is a neologism coined in Yucatec Maya, to mean "count of days" (Coe 1992). The various names of this calendar as used by Precolumbian Maya peoples are still debated by scholars. The Aztec calendar equivalent was called Tonalpohualli, in the Nahuatl language.

The tzolk'in calendar combines twenty day names with the thirteen numbers of the trecena cycle to produce 260 unique days. It is used to determine the time of religious and ceremonial events and for divination. Each successive day is numbered from 1 up to 13 and then starting again at 1. Separately from this, each day is given a name in sequence from a list of 20 day names:

Tzolk'in calendar: named days and associated glyphs

Seq. No. 1	Day Name 2	Glyph example 3	16th C. Yucatec 4	reconstructed Classic Maya 5	Seq. No. 1	Day Name 2	Glyph example 3	16th C. Yucatec 4	reconstructed Classic Maya 5
01	Imix'		Imix	Imix (?) / Ha' (?)	11	Chuwen		Chuen	(unknown)
02	Ik'		Ik	Ik'	12	Eb'		Eb	(unknown)
03	Ak'b'al		Akbal	Ak'b'al (?)	13	B'en		Ben	(unknown)
04	K'an		Kan	K'an (?)	14	Ix		Ix	Hix (?)
05	Chikchan		Chicchan	(unknown)	15	Men		Men	(unknown)
06	Kimi		Cimi	Cham (?)	16	K'ib'		Cib	(unknown)
07	Manik'		Manik	Manich' (?)	17	Kab'an		Caban	Chab' (?)
08	Lamat		Lamat	Ek' (?)	18	Etz'nab'		Etznab	(unknown)
09	Muluk		Muluc	(unknown)	19	Kawak		Cauac	(unknown)
10	Ok		Oc	(unknown)	20	Ajaw		Ahau	Ajaw
NOTES: The sequence number of the named day in the Tzolk'in calendar Day name, in the standardised and revised orthography of the Guatemalan Academia de Lenguas Mayas An example glyph (logogram) for the named day. Note that for most of these several different forms are recorded; the ones shown here are typical of carved monumental inscriptions (these are "cartouche" versions) Day name, as recorded from 16th century Yukatek Maya accounts, principally Diego de Landa; this orthography has (until recently) been widely used In most cases, the actual day name as spoken in the time of the Classic Period (ca. 200–900) when most inscriptions were made is not known. The versions given here (in Classic Maya, the main language of the inscriptions) are reconstructed based on phonological evidence, if available; a '?' symbol indicates the reconstruction is tentative.

Some systems started the count with 1 Imix', followed by 2 Ik', 3 Ak'b'al, etc. up to 13 B'en. The trecena day numbers then start again at 1 while the named-day sequence continues onwards, so the next days in the sequence are 1 Ix, 2 Men, 3 K'ib', 4 Kab'an, 5 Etz'nab', 6 Kawoq, and 7 Ajau. With all twenty named days used, these now began to repeat the cycle while the number sequence continues, so the next day after 7 Ajaw is 8 Imix'. The repetition of these interlocking 13- and 20-day cycles therefore takes 260 days to complete (that is, for every possible combination of number/named day to occur once).

Origin of the Tzolk'in

The exact origin of the Tzolk'in is not known, but there are several theories. One theory is that the calendar came from mathematical operations based on the numbers thirteen and twenty, which were important numbers to the Maya. The numbers multiplied together equal 260. Another theory is that the 260-day period came from the length of human pregnancy. This is close to the average number of days between the first missed menstrual period and birth, unlike Naegele's rule which is 40 weeks (280 days) between the last menstrual period and birth. It is postulated that midwives originally developed the calendar to predict babies' expected birth dates.

A third theory comes from understanding of astronomy, geography and paleontology. The mesoamerican calendar probably originated with the Olmecs, and a settlement existed at Izapa, in southeast Chiapas Mexico, before 1200 BC. There, at a latitude of about 15° N, the Sun passes through zenith twice a year, and there are 260 days between zenithal passages, and gnomons (used generally for observing the path of the Sun and in particular zenithal passages), were found at this and other sites. The sacred almanac may well have been set in motion on August 13, 1359 BC, in Izapa. Vincent H. Malmström, a geographer who suggested this location and date, outlines his reasons:

(1) Astronomically, it lay at the only latitude in North America where a 260-day interval (the length of the "strange" sacred almanac used throughout the region in pre-Columbian times) can be measured between vertical sun positions -- an interval which happens to begin on the 13th of August -- the day the peoples of the Mesoamerica believed that the present world was created; (2) Historically, it was the only site at this latitude which was old enough to have been the cradle of the sacred almanac, which at that time (1973) was thought to date to the 4th or 5th centuries B.C.; and (3) Geographically, it was the only site along the required parallel of latitude that lay in a tropical lowland ecological niche where such creatures as alligators, monkeys, and iguanas were native -- all of which were used as day-names in the sacred almanac.

Malmström also offers strong arguments against both of the former explanations.

A fourth theory is that the calendar is based on the crops. From planting to harvest is approximately 260 days.

Haab'

Haab' "months"

Name	Meaning†
Pop	mat
Wo	black conjunction
Sip	red conjunction
Sotz'	bat
Sek	?
Xul	dog
Yaxk'in	new sun
Mol	water
Ch'en	black storm
Yax	green storm
Sak	white storm
Keh	red storm
Mak	enclosed
K'ank'in	yellow sun
Muwan	owl
Pax	planting time
K'ayab'	turtle
Kumk'u	granary
Wayeb'	five unlucky days
† Jones 1984

Main article: Haab'

The Haab' was the Maya solar calendar made up of eighteen months of twenty days each plus a period of five days ("nameless days") at the end of the year known as Wayeb' (or Uayeb in 16th C. orthography). Bricker (1982) estimates that the Haab' was first used around 550 BC with the starting point of the winter solstice.

The Haab' month names are known today by their corresponding names in colonial-era Yukatek Maya, as transcribed by 16th century sources (in particular, Diego de Landa and books such as the Chilam Balam of Chumayel). Phonemic analyses of Haab' glyph names in pre-Columbian Maya inscriptions have demonstrated that the names for these twenty-day periods varied considerably from region to region and from period to period, reflecting differences in the base language(s) and usage in the Classic and Postclassic eras predating their recording by Spanish sources.

Each day in the Haab' calendar was identified by a day number in the month followed by the name of the month. Day numbers began with a glyph translated as the "seating of" a named month, which is usually regarded as day 0 of that month, although a minority treat it as day 20 of the month preceding the named month. In the latter case, the seating of Pop is day 5 of Wayeb'. For the majority, the first day of the year was 0 Pop (the seating of Pop). This was followed by 1 Pop, 2 Pop as far as 19 Pop then 0 Wo, 1 Wo and so on.

As a calendar for keeping track of the seasons, the Haab' was a bit inaccurate, since it treated the year as having exactly 365 days, and ignored the extra quarter day (approximately) in the actual tropical year. This meant that the seasons moved with respect to the calendar year by a quarter day each year, so that the calendar months named after particular seasons no longer corresponded to these seasons after a few centuries. The Haab' is equivalent to the wandering 365-day year of the ancient Egyptians. Some argue that the Maya knew about and compensated for the quarter day error, even though their calendar did not include anything comparable to a leap year, a method first implemented by the Romans.

Wayeb'

The five nameless days at the end of the calendar, called Wayeb', were thought to be a dangerous time. Foster (2002) writes "During Wayeb, portals between the mortal realm and the Underworld dissolved. No boundaries prevented the ill-intending deities from causing disasters." To ward off these evil spirits, the Maya had customs and rituals they practiced during Wayeb'. For example, people avoided leaving their houses or washing or combing their hair.

Calendar Round

Main article: Calendar Round

Neither the Tzolk'in nor the Haab' system numbered the years. The combination of a Tzolk'in date and a Haab' date was enough to identify a date to most people's satisfaction, as such a combination did not occur again for another 52 years, above general life expectancy.

Because the two calendars were based on 260 days and 365 days respectively, the whole cycle would repeat itself every 52 Haab' years exactly. This period was known as a Calendar Round. The end of the Calendar Round was a period of unrest and bad luck among the Maya, as they waited in expectation to see if the gods would grant them another cycle of 52 years.

Long Count

Detail showing three columns of glyphs from 2nd century CE La Mojarra Stela 1. The left column gives a Long Count date of 8.5.16.9.9, or 156 CE. The two right columns are glyphs from the Epi-Olmec script.

Main article: Mesoamerican Long Count calendar

Since Calendar Round dates can only distinguish in 18,980 days, equivalent to around 52 solar years, the cycle repeats roughly once each lifetime, and thus, a more refined method of dating was needed if history was to be recorded accurately. To measure dates, therefore, over periods longer than 52 years, Mesoamericans devised the Long Count calendar.

The Maya name for a day was k'in. Twenty of these k'ins are known as a winal or uinal. Eighteen winals make one tun. Twenty tuns are known as a k'atun. Twenty k'atuns make a b'ak'tun.

The Long Count calendar identifies a date by counting the number of days from the Mayan creation date 4 Ahaw, 8 Kumk'u (August 11, 3114 BC in the proleptic Gregorian calendar or September 6 in the Julian calendar). But instead of using a base-10 (decimal) scheme like Western numbering, the Long Count days were tallied in a modified base-20 scheme. Thus 0.0.0.1.5 is equal to 25, and 0.0.0.2.0 is equal to 40. As the winal unit resets after only counting to 18, the Long Count consistently uses base-20 only if the tun is considered the primary unit of measurement, not the k'in; with the k'in and winal units being the number of days in the tun. The Long Count 0.0.1.0.0 represents 360 days, rather than the 400 in a purely base-20 (vigesimal) count.

Table of Long Count units

Days	Long Count period	Long Count period	Approx solar years
1	= 1 K'in
20	= 20 K'in	= 1 Winal	0.055
360	= 18 Winal	= 1 Tun	1
7,200	= 20 Tun	= 1 K'atun	19.7
144,000	= 20 K'atun	= 1 B'ak'tun	394.3

There are also four rarely-used higher-order cycles: piktun, kalabtun, k'inchiltun, and alautun.

Since the Long Count dates are unambiguous, the Long Count was particularly well suited to use on monuments. The monumental inscriptions would not only include the 5 digits of the Long Count, but would also include the two tzolk'in characters followed by the two haab' characters.

Galactic astrologer Raymond Mardyks contributes that the synodic cycle of Jupiter and Saturn averages out to a mean of 7254 days. This is 54 days more than a katun (7200 days). On pp.71-73 of the Dresden Codex, there is what has been called the 54-Series (Forstemann 1905). These pages contain a compilation of multiples of 54, up until 702 (13 x 54). There continues multiples of 702, until 14040 is reached (20 x 702 260 x 54). Higher multiples of 14040 are suggested. The numbers 54, 702 and 14040 are emphasized on these pages. These are the necessary number of additional days from the mean Jupiter/Saturn synods for cycles of 1-katun, 13-katun and 13-baktun, respectively. This indicates a verifiable astronomical basis for what the Mayanists now call the "Long-Count" and specifically also the 13-baktun cycle, such as the one anticipated to conclude on December 21/23,2012.

The Mesoamerican Long Count calendar forms the basis for a New Age belief, first forecast by José Argüelles, that a significant event will take place on or about December 21, 2012, a forecast that mainstream Mayanist scholars consider a misinterpretation, yet is commonly referenced in pop-culture media as the 2012 meme.

For example, Sandra Noble, executive director of the Mesoamerican research organization FAMSI, notes that "[f]or the ancient Maya, it was a huge celebration to make it to the end of a whole cycle". However, she considers the portrayal of December 2012 as a doomsday or cosmic-shift event to be "a complete fabrication and a chance for a lot of people to cash in."

Venus Cycle

Another important calendar for the Maya was the Venus cycle. The Maya were skilled astronomers, and could calculate the Venus cycle with extreme accuracy. There are six pages in the Dresden Codex (one of the Maya codices) devoted to the accurate calculation of the heliacal rising of Venus. The Maya were able to achieve such accuracy by careful observation over many years. There are various theories as to why Venus cycle was especially important for the Maya, including the belief that it was associated with war and used it to divine good times (called electional astrology) for coronations and war. Maya rulers planned for wars to begin when Venus rose. The Maya also possibly tracked other planets’ movements, including those of Mars, Mercury, and Jupiter.

See also

• Maya civilization
• Maya religion
• Mesoamerican calendars
• Aztec calendar
• Tres Zapotes Stela C
• José Argüelles
• Mayanism
• Lunar calendar
• Calendar round
• 2012 Doomsday Prediction

References

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Thompson, J. Eric S. (1971). Maya Hieroglyphic Writing: An Introduction. Civilization of the American Indian Series, No. 56 (3rd ed.). Norman: University of Oklahoma Press. ISBN 0-806-10447-3. OCLC 275252. {{cite book}}: templatestyles stripmarker in |author= at position 1 (help)CS1 maint: numeric names: authors list (link)

Tozzer, Alfred M. notes, trans., ed. (1941). Landa's Relación de las cosas de Yucatán: a translation. Papers of the Peabody Museum of American Archaeology and Ethnology, Harvard University vol. 18. Charles P. Bowditch and Ralph L. Roys (additional trans.) (translation of Diego de Landa's Relación de las cosas de Yucatán [orig. ca. 1566], with notes, commentary, and appendices incorporating translated excerpts of works by Gaspar Antonio Chi, Tomás López Medel, Francisco Cervantes de Salazar, and Antonio de Herrera y Tordesillas. English ed.). Cambridge, MA: Peabody Museum of Archaeology and Ethnology. OCLC 625693. {{cite book}}: templatestyles stripmarker in |editor= at position 1 (help)CS1 maint: multiple names: editors list (link) CS1 maint: numeric names: editors list (link)

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External links

• Today's Mayan date in pictorial form
• Maya Calendar notes by M. Finlay, Maya Astronomy (Uses the proleptic Gregorian calendar.)
• Maya Cycles of Time at Convergence
• The Maya Calendar by the Maya World Studies Center in Yucatán Mexico
• Maya Calendar and Links on diagnosis2012.co.uk (The calculator uses the proleptic Gregorian calendar, with a number of links to other Maya calendar sites.)
• Interactive Maya Calendars

• Day Symbols of the Maya Year at Project Gutenberg 1897 text by Cyrus Thomas
• Maya Calendar, Date conversions, contemporary year version, Tzolkin and Haab day in Calendar Rounds