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Nancy McNelly's Calendar Notes

Introduction

Not all the glyphs noted in the chart above invariably appear in the date; the long count and the calendar round are almost always included, but other series or glyphs within series are not always present. There are also two relatively rare cycles that aren't discussed here: the 819 day count and a 7 day cycle. (I'll get around to adding them eventually).

In addition, while the order of the glyphs given above is the general case, individual glyphs may be smaller (the ISIG can be one column wide), larger (the long count glyphs can each occupy two columns, especially when the head variants of the numbers are used), or can be compressed or combined so that two glyphs occupy a single glyph block.

The Initial Series

The Long Count

The long count gives the total number of days passed since the Maya zero date in 3114 BC (either JD# 584,285 or JD#584,283). It begins with what is known as the Initial Series Introductory Glyph (ISIG), the form of which is constant, varying in the sign for the "patron", which is specific to the month in which the count takes place.
[ISIG image]

Each glyph that follows represents a period of time, preceded by a coefficient giving number of times each period has passed since the starting date. When one of the shorter time periods accumulates enough days to equal the longer period preceding it, the longer period's coefficient goes up by 1, and the shorter period's resets to zero (rather like a car odometer turning over).

1 Bak'tun = 20 K'atun = 144,000 days
1 K'atun = 20 Tun =7,200 days
1 Tun = 18 Winal = 360 days
1 Winal = 20 K'in = 20 days
1 K'in = 1 day

In modern notation the Long Count is expressed simply by numbers. For instance, Monday, Jan. 1, 1996 was 1,865,799 days after the starting date, or 12 bak'tun, 19 k'atun, 2 tun, 13 winal, and 19 k'in. This would be written as 12.19.2.13.19.

The Calendar Round

                Haab            Days

                Pop                     Imix
                Wo                      Ik'
                Sip                     Ak'bal
                Sotz'                   K'an
                Tzek                    Chikchan
                Xul                     Kimi
                Yaxk'in                 Manik'
                Mol                     Lamat
                Ch'en                   Muluk
                Yax                     Ok
                Sak                     Chuwen
                Keh                     Eb
                Mak                     Ben
                K'ank'in                Ix
                Muwan                   Men
                Pax                     Kib
                K'ayab                  Kaban
                Kumk'u                  Etz'nab
                Wayeb                   Kawak           
                                        Ahaw

The Long Count fixes the date in firmly in time; the Maya also used repeating cycles of time. We also do this as well - in the date given above Monday, January, and the 1st of the month are all dates that repeat at set intervals. The 365 day Mayan "year" (haab) was made up of 18 20-day "months" and one 5-day month, which repeat in much the same way. Our 1st of January in 1996 would be their 7th day of K'ank'in, and the following day, Jan. 2, would be 8 K'ank'in.

Similarly, as with our 7 day week, there is a recurring cycle of 20 different days. The Maya added to this a repeating 13 day cycle, and, together, these two cycles are now make up the tzol k'in.

January 1, 1996 fell on the 4th day of the 13 day cycle and the 19th day of the 20 day cycle: 4 Kawak. Because the two cycles have different lengths, Kawak will occur again in 20 days and the 4th in 13. It will take 260 days before another
4 Kawak comes to pass.

So our date, Jan. 1, 1996, can now be recorded as
12.19.2.13.19 4 Kawak 7 K'ank'in.

A final note: the last day of each month was not written as the 20th (or in the case of Wayeb, the 5th) but rather using a combination of the glyph for the next month and sign for "chum", the "seating" glyph. The example given below is how the last day of Wayeb would be written - as the seating of the month Pop.
[image]

The Supplementary Series

Night Gods

There was also a 9 day cycle, expressed by glyphs traditionally called G and F. Glyph G represents the name of the one of the "night gods" in the cycle of nine. F is translated as "tied on the white headband", or "ruled"; this glyph was sometimes combined with glyph G or left out altogether.

The Lunar Series

The Maya sometimes included information about the state of the moon on a given date. The glyphs associated with this lunar information are traditionally called E, D, C, X, B, and A. E and D together give the age of the moon (i.e., how many days have passed since the last new moon). If fewer than 20 days have passed, glyph D alone appears, with a coefficient before it equal to the number of days that have passed. If the moon is more than 20 days old, glyph E is added before D, with a coefficient equal to the number of days over 20.

Glyph C gives the number of the position of present lunation (lunar cycle) in a poorly-understood repeating cycle of 6 lunations. Glyph X is the name of the lunation, and glyph B is "u k'aba", meaning "its name". Glyph A is the length of the particular lunation, which the Maya gave as either 29 or 30 days. Thus glyph A consists of the moon "k'al" (20) sign plus a coefficient of either 9 or 10.

Other Cycles

As stated above, these are not the only cycles given in Mayan dates, but simply the most common ones.