Unlike the present prevailing idea of linearly running time, many ancient peoples around the world have thought of time as cyclic, which was particularly common in pre-Columbian Mesoamerica (Gillan 2019). “The Aztecs, among other groups, [such as the Mayans], believed in a succession of world ages and they depicted those ages on [the Calendar Stone]” (Andrews 1998:21).
Cyclic time

According to one version of the story, which is also analogous to the Mayan understanding of time, the Calendar Stone of the the Aztecs represents four ended eras or suns and the fifth one that is lasting now in the middle (George 2004:25; McDonald 2013). Each of the four rectangles standing for the four eras/suns additionally includes a number 4 in the forms of 4 dots or beads, which is quite significant while reading the glyphs (Aztekayolokalli 2018). Accordingly, 4 (as there are four dots) Jaguar is the oldest era of creation, supposedly between 956-280 BC (McDonald 2013). Giants who populated the Earth in that era were devoured by jaguars as they had not performed their duties to the gods (Andrews 1998:21; McDonald 2013). The next era – 4 Wind, ruled by the god Ehecatl – lasted for 364 years and it had monkey men in some versions, who were carried away and destroyed by hurricanes (Ibid.). 4 Rain was ruled by a water deity, Tlaloc, and it ended when its denizens, who were near human beings, were destroyed by the rain and fire (probably a volcano eruption) and supposedly eaten by turkeys (Ibid.). The last date – 4 Water – was the era ruled by the goddess Chalchihuiticue and destroyed by a 52-year flood and within which men drowned and maybe turned into fish (Ibid.).

The present creation (the fifth era) began on 4 Movement/Earthquake in around 1195 AD (McDonald 2013). Tonatiuh, the sun god and Tlaltecuhtli, the Earth Monster, were both created for this era by means of their own bloody sacrifice (McDonald 2013; “Tlaltecuhtli” 2019). This current creation was meant to be stable on the condition that the blood sacrifice was continuously made to the gods and it could probably last forever (Ibid.). Constant penitent sacrifice of human blood was therefore required for this era so the symbolism shown in the Sunstone is apparently all about the Aztec current world (Ibid.). By means of the Sunstone it was foretold that if the blood sacrifices had ceased, the world would have ended in earthquakes (Andrews 1998:21; McDonald 2013). These are some pretty vivid and scarily specific cataclysms responsible for the final destruction of the following eras but the most significant is the very central part of the Calendar Stone, as it stands for the current world and possible circumstances of its end (McDonald 2013).
If it is the Earth, where is the Sun?
Although the central face of the Calendar Stone may not represent Tonatiuh (see: Faces of the Fifth Sun in the World of the Aztecs) the image of the Sun is very present in the Calendar Stone (Aztekayolokalli 2018). The Sun is, however, hidden for those who do not want to see it (Ibid.).

In artistic representation of Tonatiuh, where he is wearing eagle feathers, there are direct connections between the Sun and an eagle (Aztekayolokalli 2018; “Tōnatiuh” 2020). It is “relating to the belief that an eagle is a reference to the ascending and descending eagle talons, a visual metaphor for capturing the heart or life force of a person. This particular form of symbolism points to ritual of human sacrifice, which was associated with Tonatiuh and his devouring of the hearts of victims” (“Tōnatiuh” 2020). Hence the sacrifice of human heart offered to the Sun was called the Eagle Cactus Fruit (McDonald 2013). Tonatiuh‘s symbolic association with the eagle [also] alludes to the Aztec belief of his journey as the Sun, […] travelling across the sky each day, where he descended in the west and ascended in the east” (“Tōnatiuh” 2020).
Accordingly, Tonatiuh may have been represented in the Calendar Stone in its zoomorphic disguise (Aztekayolokalli 2018). If so, where is it? Just in the center, caught in its flight (Ibid.).

In order to discern it, one should look beyond the both elements building up its picture, the goddess Tlaltecuhtli and the Nahui-Ollin glyph (Aztekayolokalli 2018). There is the eagle’s beak sticking out of the Earth and pointing up to the sky, in the direction of the date of 13 Reed (Ibid.). There are its talons being at once Tlaltecuhtli’s claws grasping human hearts and tail feathers, just below the round Face of the Earth (Ibid.). The eagle’s wings are in turn shaped by the four “wings’ of the cosmic Butterfly, and outspread to four corners of the universe (Ibid.).

The Sun is then superimposed over the shape of the Butterfly, and subsequently, they are both superimposed over the Face of Earth – astronomical event that takes place every year on July 26th, when the Sun is directly above Mexico City, in its zenith (Aztekayolokalli 2018).
Combined worlds
In the deeply carved background of the ring surrounding 4 Movement glyph, there are a few smaller date glyphs (McDonald 2013). On the right of the pointer at the top, there is the date 1 Flint Knife (Ibid.). On the left, there is a headdress glyph (Ibid.), which is interpreted as the name of Montezuma (Stuart 2016).

Hence, some scholars ascribe the Calendar Stone to the last emperor of the Aztecs (McDonald 2013). At the bottom of the same field, adjacent to the Nahui-Oliln glyph, there are also 7 Monkey (on the right) and 1 Rain (on the left) (Stuart 2016; McDonald 2013). These dates may refer to actual historical milestones in Aztec history (Ibid.). For instant, 1 Flint is likely to be the calendar name of Huitzilopochtli (Stuart 2016). As the god is the patron of the Aztecs’ city of Tenochtitlan, it may refer to the date when the Mexica tribe left their homeland, a legendary Aztlan, to found their new capital, which is now Mexico City (McDonald 2013). Accordingly, the Calendar Stone would also contain historic records (Ibid.).
Xiuhpohualli and Tōnalpōhualli
The Mesoamerican “calendar consisted of a 365-day calendar cycle called Xiuhpohualli (year count) and a 260-day ritual cycle called Tōnalpōhualli (day count). These two cycles together formed a 52-year calendar round. The Xiuhpohualli is considered to be the agricultural calendar, since it is based on the Sun” (Gillan 2019), whereas Tōnalpōhualli is regarded more in a sacred dimension of time counting (Ibid.).

“[The] Aztecs divided their year into 18 months of 20 days plus 5 days at the end” (Noble 2009:51). Some scholars see the reference to Xiuhpohualli in the Calendar Stone, representing 20 days of each of 18 months of the Aztec year in its second ring, whereas additional 5 days of the year are said to be found as 5 stone bosses around the Nahui-Ollin glyph (Noble 2009:51; see Gillan 2019; “Aztec Calendar” 2020). However, according to others, these 5 signs refer to the five suns; the four gone and the one, which is currently lasting in the current era (McDonald 2013; Aztekayolokalli 2018). Although the same sings may have got a double meaning, it is probable that only one of the two significant Mesoamerican calendars has been depicted by the Aztecs in the Sunstone (Ibid.). It is Tōnalpōhualli (day count).
Tōnalpōhualli (day count)
A ring of 20-day names circles the key image of the central creation in the Calendar Stone (McDonald 2013). The cycle starts slightly to the left of the pointer above the central face; so the cycle begins with the glyph of a Crocodile and ends with the glyph of a Flower (McDonald 2013; Aztekayolokalli 2018). Accordingly, the first day is represented by a Crocodile or an Alligator (McDonald 2013). The next to the left is Wind (Ibid.). After that a House, Lizard, Serpent, Death, Deer, Rabbit, Water, Dog, Monkey, Grass, Reed, Jaguar, Eagle, Vulture, Movement (Earthquake), Flint knife, Rain and finally a Flower (McDonald 2013; Aztekayolokalli 2018; “Aztec Calendar” 2020). To the right, the glyphs representing the Movement and Flint knife are depicted in miniature, compared to their larger characters around the central face (McDonald 2013). Additionally, “each of the day signs also bears an association with one of the four cardinal directions” (“Aztec Calendar” 2020).

That cycle of 20-day names consisted of a 260-day period (McDonald 2013; Aztekayolokalli 2018), which “was recorded in 13-day cycles” (“Aztec Calendar” 2020). It means that “each day [was] signified by a combination of a number from 1 to 13 and one of the twenty day signs. With each new day, both the number and day sign would be incremented: 1 Crocodile is followed by 2 Wind, 3 House, 4 Lizard, and so forth up to 13 Reed, after which the cycle of numbers would restart (though the twenty day signs had not yet been exhausted) resulting in 1 Jaguar, 2 Eagle, and so on, as the days immediately following 13 Reed. This cycle of number and day signs would continue similarly until the [twentieth] week, which would start on 1 Rabbit, and end on 13 Flower. It would take a full 260 [20×13] days for the two cycles, [where twenty day signs are multiplied by thirteen numbers] to realign and repeat the sequence back on 1 Crocodile” (Ibid.). Accordingly, the whole cycle “was broken up into 20 periods, [or 20-day names] of 13 days each, which was reflected in two interlocking wheels in this 260-day ritual calendar” (Gillan 2019).


This round of days was not meant by the Aztecs to depict an actual date but rather to represent the counting of time itself (McDonald 2013). The 260-day ritual calendar was an important characteristic of all Mesoamerican pre-Colombian cultures (Ibid.). Apparently, “it originated by ancient peoples observing that the [Sun] crossed a certain zenith point near the Mayan city of Copan, every 260 days” (Gillan 2019). Yet for the Aztecs it was not related to any solar or astronomical calendar features as it seems (McDonald 2013). Most likely it could have been related to the length of pregnancy (9 months) in correlation with the period of the earth’s translation around the Sun in a 365.25 days of the solar year (McDonald 2013; Aztekayolokalli 2012; “Aztec Calendar” 2019). This idea is confirmed by the fact that Mesoamerican peoples named their children after the day name of their birth in this ritual calendar (McDonald 2013). “When the child was born he or she was given the name and number of that particular 24 hour piece of time. The ancestors could identify the potential, qualities and capabilities that existed in that space of time, and this was the basis of his/her responsibility to everybody and everything that surrounded them. [In this context], mother and father were responsible for insuring their child grew up recognizing and knowing its potential and capacities and thus its responsibilities by maintaining the rhythm in which it was born” (Aztekayolokalli 2012).
Quetzalcoatl and Xolotl
The next ring of carvings consists of a repeated design of 5 dots, called quincunx, which are inscribed in little squares (McDonald 2013). After scholars they seem to represent preciousness or maybe jadeite (Ibid.). An archaeologist, Nicoletta Maestri (2019) writes they represent the five-day Aztec week in each square. Aztekayolokalli (2018), however, interprets that symbol differently. He claims that 5-dot symbol represents the five movements of Venus around the Sun in a period of eight years (Ibid.). The last number comes from 8 triangular signs set upon the ring of quincunx, which can be interpreted as rays of the Sun (McDonald 2013; Aztekayolokalli 2018; Maestri 2019).

“Known to the Mesoamericans as a bright star, […] Venus was especially important in [their] religious and agricultural calendar with its average 584-day cycle being carefully observed and precisely calculated. Even the architectural layout of [important Mesoamerican cities] were built and aligned in accordance with the appearance of Venus at particular moments during its cycle. […] Mesoamerican astronomers recorded that the planet appears for 236 days as the morning star in the east, then sinks below the horizon for 90 days, and reappears for 250 days as the evening star in the west before disappearing again for 8 days before restarting the cycle over again. In actual fact, Venus can be seen with the naked eye for approximately 263 days in each spell, and it is not known quite why or how the ancient astronomers had arrived at their particular calculations” (Cartwright 2017). And it is probably a coincidence that this number of days when Venus is visible also overlaps with the 260-day ritual calendar. However, there is no evidence confirming that the Mesoamerican day count, Tōnalpōhualli, was related in any way to the appearance of Venus.


As the morning star, Venus was described as the Beginning of the Daylight, and as the evening star – it was named the Companion of the Sun (Aztekayolokalli 2018). “Each aspect of Venus – morning and evening – was manifested in the form of two ancient Mesoamerican gods: the feathered-serpent Quetzalcoatl and his canine companion Xolotl. Quetzalcoatl represented Venus as the morning star, and Xolotl represented it as the evening star” (Cartwright 2017; see Aztekayolokalli 2018). Simultaneously, another Mesoamerican deity, “Tlahuizcalpantecuhtli manifested the dual aspect of the planet Venus (Ibid.). As the twin brother of Xolotl and the avatar of Quetzalcoatl, he was imagined as both and so represented the morning and evening star aspects of Venus (Ibid.).
The Moon
Going outwards, the next string or band of images in the Calendar Stone is obscure to scholars (Mc Donald 2013).

There may be some representations of feathers, beads and blood drops but it is really not clear (Mc Donald 2013). Aztekayolokalli (2018) believes the ring represents kernels of corn. There are 10 such kernels between each of the 8 sun-rays (or triangles pointing outside the center), which create a pattern looking like a lace decorating the ring (Ibid.). Additional 3 grains of corn are visible on top of the square, sticking out in the middle of the “corn lace” (Ibid.) Consequently there are 13 grains of corn altogether, and the number 13 represents the number of the Moon rises in a year cycle (Ibid.). What is more, the Moon also moves 13 degrees per day around the Earth (Ibid.).
Two encircling dragons
The final, encircling ring consists of two thick fire serpents or dragons, called Xiuhcoatl (McDonald 2013). Such imagery points to the fact that symbols of serpents are significant in Mesoamerican cultures (Ibid.). The fire serpents’ tails are at the very top with their pointed ends framing the date of 13 Reed (Ibid.).

Their bodies are divided into squared segments that have butterfly symbols (Nahui-Ollin glyphs) inside them and the serpents encircle the whole disc only to end with their open moss at the bottom of the Stone (McDonald 2013). These rather nasty looking serpent faces have noses or perhaps tongues that curl up and back (Ibid.). They are probably adorned by star signs (Ibid.). Revealed in the dragons’ mouths are two more deities, represented as two anthropomorphic heads sticking out of the animal bulks (Ibid.). Such imagery is typical of the Mayan god, Kukulcan (the equivalent of Quetzacoatl), who has been similarly represented among others in Chichen Itza (Mexico) or Mixco Viejo (Guatemala) as a feathered serpent with a human head protruding out of its open jaws. Yet the gods on the Calendar Stone are identified by archaeologists as other deities. The left god is probably the Sun god and one on the right is the fire god, Xiuhtecuhtli (Ibid.). One interesting thing about more or less human looking faces of the deities on this stone is that they all look quite ferocious (Ibid.). They have got open mouths as if screaming or biting in a hostile and aggressive manner (Ibid.).
In the margin of the Circle
But It is not the end of the mysteries of the Stone (McDonald 2013). The ragged looking edges of the Calendar Stone have some meaning as well (Ibid.).

These unfinished looking side areas depict the constellations or, as the Aztecs called them Tzitzimimeh, which means star demons (McDonald 2013; “Tzitzimitl” 2020). They were “associated with the stars and especially the stars that can be seen around the Sun during a solar eclipse. This was interpreted as the Tzitzimimeh attacking the Sun, thus causing the belief that during a solar eclipse, the tzitzimime would descend to the earth and possess men” (“Tzitzimitl” 2020). These demonic beings were terrifying to the Aztecs as they were responsible for the eclipse of the Sun and by extension for the death of the Sun and the Earth (McDonald 2013). Eclipses were the moments of terror for the populace of the Aztecs and the only thing they could do to keep the Sun moving in the sky was to feed it human hearts and blood, as much as the gods once sacrificed themselves in order to create the Sun, the Earth and the Moon (Ibid.).

Star demons were part of the Mesoamerican cosmic mythology but it does not mean that the Aztecs did not understand the eclipse phenomenon. Such an assumption would be rather peculiar, providing that Mesoamerican cultures used to reflect important astronomical events not only through their art but also in layouts of their whole cities. The Calendar Stone itself is a complex mechanism combining the Aztec multi-dimensional understanding of time with particular dates and astronomical events. And even though the Aztecs dressed most celestial bodies and events in colourful mythical costumes, they held the essential knowledge of the universe and its cosmic scheme. It is probable, however, that such knowledge was ultimately reserved for the Aztec elite, namely emperors and priests, in order to keep control over the peoples within the Empire and to threaten their enemies.
Although the film tells the story of the Mayas, it looks more like a portrayal of the Aztec Empire just in the eve of the Spanish Conquest (see: Von Tunzelmann A. (2008). The fragment shows the solar eclipse and the reason of the Aztec dominance due to their astronomical knowledge. Source: vsprlnd25 (2012). In: vsprlnd25 Youtube Channel.
Such an idea has been well represented in one of the scenes from the film Apocalypto, directed by Mel Gibson (2006). Although the director has meant to represent the culture of the Maya, its interpretation rather fits the Aztecs and their ceremony of massive human sacrifice in the city of Tenochtitlan. In the scene, when the eclipse of the Sun takes place, darkness falls down on the crowd at the foot of the pyramid. It looks as if the end of the world was coming. People are terrified, the next victim is stretched over the altar and waiting for cruel death. But the emperor and the High Priest are not afraid. They exchange a knowing look as if they knew what is going to happen. Another religious attendant is theatrically entering into trance, while the High Priest is assuring the gathered faithful that the gods have been sated by the offered sacrifice; hence they will spare the Sun and life. Finally, he turns to the gods asking them to let the Sun shine again. And after a while, the Sun reappears in the sky. The crowd is cheering. The Aztec elite has once again legitimized their power and right to intermediate between people and the deities.
The Stone of Tizoc
Apart from the Sunstone, probably the best and most interesting example of other Aztec stones to look at is the Stone of Tizoc (McDonald 2013). This is also because it may shed some light on the meaning on the Calendar Stone (Ibid.). By comparing both monuments, it can be seen what a masterpiece and a great accomplishment the Sunstone is (Ibid.).

The Stone of Tizoc was found buried in the Zocalo just a year after the Calendar Stone was found, namely in 1791 (McDonald 2013). Tizoc was the Aztec tlatoani (1481-1486) who came just after Axayacatl (1469-1481) (Ibid.). He was not a very successful emperor and so he did not reign very long, just about six years (Ibid.). Yet his stone is a masterwork of propaganda and cosmic imagery (Ibid.). It is proportionally thicker than the Calendar Stone but has a much simpler design on its topmost surface (Ibid.). The image there is probably meant to be a solar disc and it is very similar to the Calendar Stone (Ibid.). Although much simplified (Ibid.). There is also a carved depression in its center, which was meant to hold the blood and hearts of sacrificed warriors (McDonald 2013; “Tlaltecuhtli” 2019). Hence it is likely that this stone was used as Cuauhxicalli for holy sacrifices (McDonald 2013).

The most interesting part of the Stone of Tizoc is actually represented on its tom sides (McDonald 2013). First of all, there are fifteen repeated images of Tizoc carved in very sharp cut but fairly shallow relief on the surface (Ibid.). Tizoc is not shown as himself but rather in the guise of the god Tetzcatlipoca, known as the Smoking Mirror, or Huitzilopotchtli – the patron deity of the Aztecs (Ibid.). The scenes depict Tizoc conquering neighbouring places in the repetitive motif in which the emperor-god grasps the hair of the personified town (Ibid.) (likewise pharaohs are represented in Egypt while fighting back their enemies). In reality Tizoc had a reputation of a coward and an unsuccessful ruler (Ibid.). But the interesting thing about the Tizoc monument is that it combines historical events and places with the cosmic ones, just like the Calendar Stone (Ibid.). As such, they both serve at once as a historical document and a religious one (Ibid.). Tizoc has been shown conquering or rather claiming to have conquered real places, like Xochimilco (Ibid.). On the other hand, he has got a divine mission (Ibid.). On the surface of the sacrificial stone there is probably depicted the Sun, on the underside – the Earth Monster; in such a context, Tizoc is depicted just between them, metaphorically holding apart the Sun from the Earth (Ibid.). So this device gives a ruler the central role, not only in military expansion but in cosmic terms, just like in the Maya world, or elsewhere in other ancient cultures beyond America (Ibid.).

conquering neighbouring places in the repetitive motif
in which the emperor-god grasps the hair of the
personified town. Copyright©Archaeotravel.
The Calendar Stone is similar in its meaning to the Stone of Tizoc but even more significant (McDonald 2013). As it seems, It functions at several levels at the same time (Ibid.). It combines some historical dates with the cosmic scheme of creation and destruction of the previous worlds/eras or the suns (Ibid.). And it commands in a sense a continuation of sacrifices to the gods through its imagery and places all these variables in the mandala like scheme of really great complexity (Ibid.).
Definition of the Disc
Not all is still understood about the Calendar Stone (McDonald 2013). So great is the content and the information depicted (Ibid.). Whatever the final and exact interpretation of the Sunstone is, it gives some interesting knowledge about Mesoamerican cultures and their relation to the cosmic scheme of the universe and their deities (Ibid.). The Calendar Disc also contains “millennia of accumulated astronomical knowledge and wisdom” (Aztekayolokalli 2012). It combines historical and mythological worlds and translates their truths through various understandings of the time. “It was not just a way to keep time – it was a complete philosophy of time in which every day had a religious significance. [The Aztecs] also believed that time went in cycles – ultimately in the repeated destruction and recreation of the world” (Gillan 2019).

As Dr McDonald (2013) also believes the enormous sculpture of the Calendar Stone not only has encoded a message about the cataclysm and cosmic destruction but also the warlike imagery of the Aztec nation itself. It must have been an imposing and threatening message to those who saw it (Ibid.). There was serious intimidation going on there and cooperation must have been coerced through the art (Ibid.). The very shape of the stone itself calls to mind the ultimate human sacrifice of blood and hearts (Ibid.). This was the kind of monument which reminded the populace of Tenochtitlan and of the peripheral provinces of the Empire of the power of the gods and of the rulers and state itself (Ibid.). The destruction of the Sun and the universe hung in the balance, so obviously obeying the authorities was the best course to follow for survival (Ibid.).
Featured image: Calendar Aztec Stone in the Museo Nacional de Antropología, Mexico City. Photo by Dezalb (2018). Photo source: Free images at Pixabay.

By Joanna
Faculties of English Philology, History of Art and Archaeology.
University of Silesia in Katowice, Poland;
Cardinal Stefan Wyszyński University in Warsaw, Poland;
University College Dublin, Ireland.
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