The Maya lived in Central America, in regional municipalities comparable to the Greek city states. They were located in what is now called Mesoamerica. This region covers Central Mexico through El Salvador, Guatemala as far south as Honduras. Theirs was a Stone Age Culture, devoid of metal weapons. However, by the time of Spanish contact in the sixteenth century, the Maya had begun working with copper and gold. While the Spanish prized gold highly, the Maya venerated jade.

The Maya developed mathematics using a base of 20. Instead of ten digits like we have today, the Maya used a base number of 20. (Base 20 is vigesimal.) They also used a system of bar and dot as "shorthand" for counting. A dot stood for one and a bar stood for five. It was very easy to add and subtract using this number system, but they did not use fractions. Base twenty was also used in their calendar, which is the first major portion of this paper because calendars are developed by astronomers for keeping track of time.

The Maya developed a sophisticated calendar. The ritual calendar that developed in Mesoamerica used a count of 260 days. This calendar gave each day a name, much like our days of the week. There were 20 day names, each represented by a unique symbol. The days were numbered from 1 to 13. Since there are 20 day names, after the count of thirteen was reached, the next day was numbered 1 again. The 260-day or sacred count calendar was in use throughout Mesoamerica for centuries, probably before the beginning of writing.

Maya Day Names & Approximate Meanings

Day	Meaning	Day	Meaning
Imix	Waterlily	Chuwen	Frog
Ik'	Wind	Eb	Skull
Ak'bal	Night	Ben	Corn stalk
K'an	Corn	Ix	Jaguar
Chikchan	Snake	Men	Eagle
Kimi	Death head	Kib	Shell
Manik'	Hand	Kaban	Earth
Lamat	Venus	Etz'nab	Flint
Muluk	Water	Kawak	Storm cloud
Ok	Dog	Ahaw	Lord

The Maya also tracked a vague solar year in which they counted 365 days per year. Because they could not use fractions, the "quarter" day left over every year caused their calendar to drift with regard to the actual solar year. The 365-day year contained months were also given names. numbers 0-19 before they changed, so that the count goes Zero Pohp to 19 Pohp, then continues with Zero Wo.

Month Names and Approximate Meanings

Month	Meaning	Month	Meaning
Pohp	Mat	Yax	Green ??
Wo	??	Zak	White ??
Sip	??	Keh	Red??
Sotz'	Bat	Mak	??
Sek	??	K'ank'in	??
Xul	Dog	Muwan	Owl
Yaxk'in	New Sun	Pax	??
Mol	Water	K'ayab	Turtle
Ch'en	Black ??	Kumk'u	??

To the eighteen regular months the Maya appended a special five-day month called Wayeb composed of 5 days which were considered unnamed and unlucky. Thus the days were counted: One Imix, Zero Pohp, Two Ik, One Pohp. When the thirteenth day was reached the next day was Thirteen Ben, Twelve Pohp; then One Ix, Thirteen Pohp, Two Men, Fourteen Pohp. After Seven Ahaw, Nineteen Pohp, the next day was Eight Imix, Zero Wo.

In addition, the Maya used special glyphs to indicate time periods, the kin represented one day. Winals are periods of 20-days which we now call a month. The Tun was a year of 360 days and the K'atun was a time period of 20 years of 360 days each. As we will see later, the K'atun ending was a special time period celebrated by the Maya. It has its parallel in the modern world, the period of time which we call a decade. The Maya also counted 400-year periods called Baktuns. The Maya used these time periods in a special day count which is now called the Long count. Today a typical long count date is written thus: 9.14.12.2.17. This represents 9 baktuns, 14 k'atuns, 12 tuns, 2 winals and 17 k'ins.

[Special note: All names given here are in the new orthography developed by native Maya of Guatemala. Their system is being accepted by many various organizations of Maya and similar forms of this orthography are being adopted by other Maya groups. In actuality, this system probably makes it easier for English speakers to pronounce the actual words. Given the Maya propensity for words and language it is only a natural development.]

The Maya developed a highly complex system of writing, using pictographs and phonetic or syllabic elements. A complete discussion of their writing system is beyond the scope of this paper. Their writing was highly sophisticated, probably only members of the higher classes were able to read their symbols. The Maya carved these symbols into stone, but the most common place for writing was probably the highly perishable books they made from bark paper, coated with lime to make a fresh white surface. These "books" were screen-folded and bound with wood and deer hide. They are called codices, codex is singular. Because of their perishable nature and zealous Spanish book burning, only four codices remain today.

The contents of the codices must have varied, but some of them were evidently similar to astronomic almanacs. We have examples of a Venus table, eclipse tables in a codex in Dresden. There is a codex in Paris that seems to contain some kind of Maya Zodiac, but if it is and how it must have worked are still unknown. Another major example of Maya almanacs are present in the Madrid Codex. The fourth codex is called the Grolier and was authenticated as late as 1983. These codices probably contained much of the information used by priests or the noble class to determine dates of importance or seasonal interest. We can only speculate as to whether or not the Maya developed poetry or drama that was committed to paper. The codices probably kept track of dynastic information as well.

The Maya were quite accomplished astronomers. Their primary interest, in contrast to "western" astronomers, were Zenial Passages when the Sun crossed over the Maya latitudes. On an annual basis the sun travels to its summer solstice point, or the latitude of 23-1/3 degrees north. Most of the Maya cities were located south of this latitude, meaning that they could observe the sun directly overhead during the time that the sun was passing over their latitude. This happened twice a year, evenly spaced around the day of solstice. The Maya could easily determine these dates, because at local noon, they cast no shadow. Zenial passage observations are possible only in the Tropics and were quite unknown to the Spanish conquistadors who descended upon the Yucatan peninsula in the 16th century. The Maya had a god to represented this position of the Sun called the Diving God.

Venus was the astronomical object of greatest interest. I think it possible that the Maya knew it better than any civilization outside Mesoamerica. They thought it was more important than the Sun. They watched it carefully as it moved through its stations--it takes 584 days for Venus and the Earth to line up in their previous position as compared to the Sun. It takes about 2922 days for the Earth, Venus, the Sun, and the stars to agree. The pattern of Venus is usually reckoned at Inferior Conjunction, that time when Venus passes between the Sun and the Earth. During this period, Venus cannot be seen from Earth. It disappears for a short period that averages 8 days. When it first rises after inferior conjunction, that is when it was first spotted in the morning sky, called heliacal rising because it is rising with the sun, was the most important position of Venus. After rising, Venus will reach its greatest brilliancy then it greatest elongation west, moving quickly (in retrograde motion) away from the Sun. After that it will remain visible for about 260 days in the morning sky until it reaches superior conjunction. At this point Venus is on the opposite side of the Sun as we view it from Earth. It becomes dim, until it dips back under the horizon, only to appear on the opposite side of the sun an average of 50 days later. It then rises as a evening star and remains in the night sky about 260 days until it goes through its eastern elongation point and greatest brilliancy before arriving at Inferior Conjunction again.

The Maya made daytime observations of Venus. Venus had a psychological effect upon the Maya and other Mesoamerican cultures, it has been shown that the Maya were timing some of their wars based on the stationary points of Venus and Jupiter. Humans were sacrificed on first appearance after Superior Conjunction when Venus was at its dimmest magnitude but they most feared the first Heliacal Rising after Inferior Conjunction. In the Dresden Codex, the Maya had an almanac that displayed the full cycle of Venus. They counted five sets of 584 days, that is 2,920 days are approximately 8 years or 5 repetitions of the Venus cycle.

The Maya had a lunar component to their calendric inscriptions. After giving the pertinent information on the date according to the Maya calendar the typical Maya inscriptions contain a lunar reckoning. The lunar count was counted as 29 or 30 days, alternating. The lunar synodic period is close to 29.5 days, so by alternating their count between these two numbers the moon was carefully meshed into the calendric sequence as well. Their lunar knowledge was impressive for they also made eclipse predictions, an almanac for predicting them is contained in the Dresden Codex.

The Maya portrayed the Ecliptic in their artwork as a Double-Headed Serpent. The ecliptic is the path of the sun in the sky which is marked by the constellations of fixed stars. Here the moon and the planets can be found because they are bound, like the Earth, to the sun. The constellations on the ecliptic are also called the zodiac. We don't know exactly how fixed constellations on the ecliptic were seen by the Maya, but we have some idea of the order in some parts of the sky. We know there is a scorpion, which we equate with our own constellation of Scorpius, in this figure I believe they used the claws of Libra. It has also been found that Gemini appeared to the Maya as a pig or peccary, (a nocturnal animal in the pig family.) Some other constellations on the ecliptic are identified as a jaguar, at least one serpent, a bat, a turtle, a xoc monster--that is, shark, or a sea monster. The Pleiades were seen as the tail of the rattlesnake and is called, "Tz'ab."

The Maya evidently thought quite a bit about the Sun and they watched it trace out a path along the ecliptic. They followed it year round, presumably following its path along the horizon as well. At Chichen Itza, during sunset a sun serpent rises up the side of the stairway of the pyramid called El Castillo on the day of Spring and Autumn Equinox. It tells us that the Maya noted, not only the extremes of the Sun at the Solstices, but also the Equinoxes when the Sun appeared to rise due East or due West. In addition to the Zenial Passages mentioned earlier, ecliptic observations must have been a major portion of Maya solar observing.

The Milky Way itself was much venerated by the Maya. They called it the World Tree, which was represented by a tall and majestic flowering tree, the Ceiba. The Milky Way was also called the Wakah Chan. Wak means "Six" or "Erect". Chan or K'an means "Four", "Serpent" or "Sky". The World Tree was erect when Sagittarius was well over the horizon. At this time the Milky Way rose up from the horizon and climbed overhead into the North. The star clouds that form the Milky Way were seen as the tree of life where all life came from. Near Sagittarius, the center of our galaxy, where the World Tree meets the Ecliptic was given special attention by the Maya. A major element of the World Tree include the Kawak Monster, a giant head with a kin in its forehead. This monster was also a mountain or witz monster. A sacrificial bowl on its head contains a flint blade representing sacrifice, and the Kimi glyph that represents death. The Ecliptic is sometimes represented as a bar crossing the major axis of the world tree, making a form that is similar to the Christian Cross. On top of the World Tree we find a bird that has been called, the Principal Bird deity, or Itzam Ye. There is also evidence that shows the Sun on the World Tree as it appeared to the Maya at Winter Solstice.

During the months of winter, when the so-called "Winter" Milky Way dominates the sky, it was called the "White Boned Serpent." This part of the Milky Way passed overhead at night during the dry season. It is not brilliant like the star clouds that dominate the sky North of the equator during the months of Summer, but observers at dark locations can easily see the glow. Here the Ecliptic crosses the Milky Way again, near the constellation of Gemini which was the approximate location of the Sun during Summer Solstice. It is possible that the jaws of the White-Boned Serpent were represented by the Kawak monster head.

The Maya Kings timed their accession rituals in tune with the stars and the Milky Way. They celebrated k'atun endings approximately every twenty years. At the end of the 20-year k'atun period, Maya rulers regularly erected a stela, called a stone tree, to commemorate the event. On stone stela they depicted themselves at the time of these ceremonies dressed in costumes that contained the symbols that were associated with the World Tree. Their headdresses contained the Principal Bird Deity, in their arms they held a so-called ceremonial bar that represented the double-headed serpent of the ecliptic. By wearing the costume elements of the World Tree the Maya ruler linked himself to the sky, the gods and that essential ingredient, life. In addition, it has been found that when the k'atun ending coincided with certain planetary positions the Maya went to war to obtain captives. The cosmology of the Maya was a living, religious philosophy that permeated their lives to a degree that might seem excessive to modern people. They were astute observers, sensitive to the cyclical nature of the sun, moon and planets.

Date: Tue, 2 May 1995 13:47:27 -0400 From: "A. D. Jenkins" Subject: Re: Mayan Astronomy This document is a written summary of a lecture I gave on the topic of Maya Astronomy at the February 13, 1995, at the regular meeting of the Cuyahoga Astronomical Association. It has been edited for posting to the ASTRO list, a bitnet mailing list. Dawn Jenkins, ct411@cleveland.freenet.edu