Ollin symbol


The "Aztec Calendar Stone" is the most famous of a number of similar pre-Columbian Mesoamerican carvings. It is a 12-foot diameter, 25 ton stone, presently in the National Museum of Anthropology, Mexico. It was carved in 1479 AD, 40 years before the Spanish conquest (after 1519). Here is a photograph of the stone as it looks today. Two reconstructions of the original appearance of the Stone are shown on this page.

The themes expressed in the stone are common to cultural traditions extending back to over 2000 years earlier, through the Toltec, Maya, Olmec and related societies. The stone is less a detailed representation of the well-developed Aztec calendar system than a monument to their most important deity, the Sun god Tonatiuh. It is more correctly called the "Sun Stone."

The circular shape of the stone represents the cyclic nature of time in the Mesoamerican world view. The Aztecs were closely familiar with the regular cyclic behavior of astronomical objects like the Sun, Moon, and Venus, building on observations compiled by the highly accomplished Maya astronomers who preceded them. The two innermost concentric circular bands surrounding the complex central carving of the stone represent parts of the two primary repeating ritual calendars of Aztec religious and civic life. The smaller band contains the 20 "day signs" of the ceremonial "month." These were combined with 13 numbered days to produce a unique series of dates within a 260-day cycle called the tonalpohualli (or the tzolkin by the Maya). In contrast to most calendars, the concept of a lunar month (30 days) did not play a major role in this system.

The larger band of 52 symbols represents the 52-year duration of the "Calendar Round." Days within this cycle received unique dates by virtue of combining the tonalpohualli cycle with the 365-day solar year. In civic life, the Round was equivalent to our century. Since individuals in Aztec times rarely lived longer than 52 years, each day of their lives carried a unique calendrical marker.

The cyclic mechanism of the Mesoamerican calendar is illustrated in this video.

For more details on the calendars represented on the stone, see this web site.

Aztec Sun Stone Small

Center of the Sun Stone. (Painting by R. S. Flandes)


To sustain him in his movement across the sky and to forestall the descent of perpetual cosmic darkness and vicious demons on the Earth, the Aztecs believed they were obligated to regularly feed the Sun god human hearts and blood. The tongue-like implement extending from the god's mouth on the stone is a sacrificial flint knife of the kind used to slash open the chests of captive warriors during the ritual murders. The god's insistence on sacrifice is symbolized by the bird-like claws that clutch human hearts on either side of his face.

The close of a Round of 52 years involved a concerted nation-wide cleansing ritual, in which all fires were extinguished, followed by the symbolic rekindling of the Sun by building a fire on the opened chest of a human sacrificial victim. The Sun Stone itself was probably intended to be mounted horizontally in order to receive the hearts and blood from this and other violent ceremonies.


Beyond reflecting the calendar, the stone describes the vibrant but cataclysmic Aztec cosmology. The glaring face of the Sun god at the center of the stone (see image above) is surrounded by a six-lobed symbol for Ollin, or "movement." Also reproduced at the head of this page, the Ollin symbol is the only one of the twenty day signs to represent an abstract concept as opposed to "Reed," "Wind," or "Water," for instance. It refers to the movement of the Sun through the sky but also to the movement of the Earth in the form of destructive earthquakes.

The four squarish panels within the Ollin symbol depict the four cosmological epochs thought to have preceded the era of the Aztec empire. During each of these, the gods struggled to nurture mankind on Earth only to be defeated by a catastrophe. The date and nature of each cosmic holocaust is given in the panels: 4 Jaguar, 4 Wind, 4 Rain, and 4 Water---the numeral 4 being a bad omen.

Here is a description of the cosmological panels on the Sun Stone from Skywatchers of Ancient Mexico by Anthony F. Aveni (1980, p. 143):

"The concept of the cyclic destruction and rebirth of the world is a common theme in Mesoamerican religion and mythology. On the famous Aztec calendar stone, surrounding the face of the Sun God, about whom all periodic phenomena in nature take place, we see four rectangular panels symbolizing the destruction of the world on each of the previous epochs through which it has passed. In the most remote epoch (upper right), giants who inhabited the earth were attacked and devoured by jaguars. At the upper left, the god of wind symbolizes the hurricanes that carried away the people of the second epoch. The third cosmogonic epoch, symbolized the god of fire-rain at the lower left, was destroyed by lava and fire in a great volcanic eruption. The few survivors were those who were able to transform themselves into birds. Storms and torrential rains epitomized by the water god ending the fourth epoch (lower right panel) caused men to be changed into fishes. In the present, or fifth, epoch destruction by earthquake is said to await us."

The fifth cosmological era, when the stone was carved, began with the self-immolation of the god Nanhuatzin on behalf of mankind and his reappearance in the sky as the Sun god. Four small circles at the corners of the large Ollin symbol give the date 4 Ollin on which the transformed god, now the "Fifth Sun," began moving through the sky. But the date also predicts the earthquake catastrophe that the Aztecs believed would end the fifth cosmic epoch.


The Maya, who preceded the Aztecs but whose civilization dramatically collapsed ca. 850-950 AD, also believed in the recurring cosmic cycle of birth and destruction, although they regarded the then-current cycle as the fourth one rather than the fifth. The Maya tracked time within each cycle with a third primary calendar system, the Long Count. (The Aztecs had abandoned this device.) The Long Count assigned a unique number to each day within a cosmic cycle. Counts were expressed in a modified base-20 system, the longest unit of which was the baktun. A baktun is 20x18x20x20 = 144,000 days or 394 solar years long. Some Maya documents suggest that a cosmic creation cycle would end in a worldwide disaster after exactly 13 baktuns, or 5125 years. By cross-correlating with unique astronomical events and historical dates after the Spanish conquest, archaeologists were able to convert Long Count dates to those in the Julian (Western) calendar. The starting date of the fourth cycle (and the end of the previous one) was determined to be 11 August 3114 BC. But that implied that the end of the fourth cosmic cycle occurred on 21 December 2012!

You can find much speculation on the Internet about the meaning of the cycle turnover in December 2012, including irresponsible predictions of a Doomsday. Needless to say, that didn't happen. But the predictions were groundless to begin with. Remember that for all their skill in tracking the planets, the Mesoamerican world view was riddled with superstition, and they showed no insight regarding the true physical nature of the universe or even the size and shape of the Earth. Their writings were vague and contradictory concerning the cosmic cycles, and some inscriptions anticipate eras as much as 2020 years in an inconceivably distant future. Finally, as is obvious from the historical record, there was no worldwide cataclysm in 3114 BC, the end of the preceding cycle. And the actual apocalypse for the Maya civilization took place not in 2012 but over 1100 years before and from more mundane causes.

For an extensive discussion of the scientific facts concerning the 2012 termination of the Maya cosmic cycle, see the 2012Hoax website.


The Aztec Sun Stone beautifully captures the colorful, if grim, Mesoamerican world view. This is a fascinating example of a pre-scientific cosmology. The intense, if often unconscious, desire to find human meaning in the universe and the absence of stringent standards for evidence in pre-scientific cultures are the reasons that their world views are so different from ours. The shared features of such world views include these:


The images above and below are artists' reconstructions of the stone's original appearance, including its likely coloration. The image below was copied from It is an interpretation by F. Devalos from National Geographic. An interactive, interpretive map of the calendar stone used to be posted at Maybe it will reappear somewhere else soon.

Aztec Sun Stone

Last modified December 2020 by rwo

Text, other than the Aveni quote, copyright © 1999-2020 Robert W. O'Connell. All rights reserved. These notes are intended for the private, noncommercial use of students enrolled in Astronomy 1210 at the University of Virginia.