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[Solomon]

The Thirteen Towers constitute an ancient solar observatory

Science 2 March 2007:
Vol. 315. no. 5816, pp. 1239 - 1243
DOI: 10.1126/science.1136415
Chankillo: A 2300-Year-Old Solar Observatory in Coastal Peru

van Ghezzi1,2,3* and Clive Ruggles4

The Thirteen Towers of Chankillo run north to south along a low ridge within a fourth-century B.C.E. ceremonial complex in north coastal Peru. From evident observing points within the adjacent buildings to the west and east, they formed an artificial toothed horizon that spanned?almost exactly?the annual rising and setting arcs of the Sun. The Chankillo towers thus provide evidence of early solar horizon observations and of the existence of sophisticated Sun cults, preceding the Sun pillars of Incaic Cusco by almost two millennia.

1 Instituto Nacional de Cultura, Avenida Javier Prado Este 2465, Lima 41, Peru.
2 Pontificia Universidad Catolica del Peru, Avenida Universitaria Cuadra 18, Lima 32, Peru.
3 Yale University, 51 Hillhouse Avenue, New Haven, CT 06511, USA.
4 School of Archaeology and Ancient History, University of Leicester, Leicester LE1 7RH, UK.

* To whom correspondence should be addressed. E-mail:


When viewed from the western observation point, the Sun appears to the left of the left-most tower

The Thirteen Towers of Chankillo
t comprises of a group of 2,300-year-old structures, known as the Thirteen Towers, which are found in the Chankillo archaeological site, Peru.

The towers span the annual rising and setting arcs of the Sun, providing a solar calendar to mark special dates.

The study is published in the journal Science.

Clive Ruggles, professor of archaeoastronomy at Leicester University, UK, said: "These towers have been known to exist for a century or so. It seems extraordinary that nobody really recognised them for what they were for so long.

"I was gobsmacked when I saw them for the first time - the array of towers covers the entire solar arc."

The Thirteen Towers of Chankillo run from north to south along the ridge of a low hill within the site; they are relatively well-preserved and each has a pair of inset staircases leading to the summit.

The rectangular structures, between 75 and 125 square metres (807-1,345 sq ft) in size, and are regularly spaced - forming a "toothed" horizon with narrow gaps at regular intervals.

About 230m (750ft) to the east and west are what scientists believe to be two observation points. From these vantages, the 300m- (1,000ft-) long spread of the towers along the horizon corresponds very closely to the rising and setting positions of the Sun over the year.

For example," said Professor Ruggles, "if you were stood at the western observing point, you would see the Sun coming up in the morning, but where it would appear along the span of towers would depend on the time of the year."

"So, on the summer solstice, which is in December in Peru, you would see the Sun just to the right of the right-most tower; for the winter solstice, in June, you would see the Sun rise to the left of the left-most tower; and in-between, the Sun would move up and down the horizon."

This means the ancient civilisation could have regulated a calendar, he said, by keeping track the number of days it took for the Sun to move from tower to tower.

Sun cults
The site where the towers are based is about four square kilometres (1.5 square miles) in size, and is believed to be a ceremonial centre that was occupied in the 4th Century BC. It is based at the coast of Peru in the Casma-Sechin River Basin and contains many buildings and plazas, as well as a fortified temple that has attracted much attention.

The authors of the paper, who include Professor Ivan Ghezzi of the National Institute of Culture, Peru, believe the population was an ancient Sun cult and the observatory was used to mark special days in their solar calendar.


A lot of attention at the Chankillo site has focused on what is thought to be a fortified temple.

Professor Ruggles said: "The western observing point, and to some extent, the eastern one, are very restricted - you couldn't have got more than two or three people watching from them. And all the evidence suggests that there was a formal or ceremonial approach to that point and that there were special rituals going on there.

"This implies that you have someone special - the priests perhaps - who watched the Sun rise or set, while in the plaza next door, the crowds were feasting and could see the Sun rise, but not from that special perspective.

Written records suggest the Incas were making solar observations by 1500 AD, and that their religion centred on Sun worship.


Professor Clive Ruggles
MA DPhil FSA
Professor of Archaeoastronomy

Biography
Having had a varied academic career passing from astronomy to archaeology to computer science and then back to archaeology again, Clive's research interests centre upon people's interests in, perceptions of, and uses of the sky and celestial objects in various social contexts. These topics are encapsulated in the fields of study that have become known as archaeastronomy and ethnoastronomy, and in 1999 Clive was appointed Professor of Archaeoastronomy within the School, apparently the first such post in the world. He is currently working on a critical synthesis of European archaeoastronomy funded by a Major Research Fellowship from the Leverhulme Trust. He also has ongoing field projects in Polynesia and Peru.

Within the UK, Clive is President of the Prehistoric Society and a Fellow of the Society of Antiquaries. He is also Chair of the Astronomical Heritage Committee of the Royal Astronomical Society. On the international stage he is Vice-President of Commission 41 (History of Astronomy) of the International Astronomical Union and Past President of the International Society for Archaeoastronomy and Astronomy in Culture.

His recent books include Astronomy in Prehistoric Britain and Ireland (Yale UP, 1999), which has received excellent reviews and a major award in the US, and Ancient Astronomy: An Encyclopedia of Cosmologies and Myth (ABC-CLIO, 2005). He was also assistant editor for Songs from the Sky: Indigenous Astronomical and Cosmological Traditions of the World (Ocarina Books, 2005). Forthcoming books include Cultural Astronomy in New World Cosmologies, edited with Gary Urton (UP of Colorado), The Heavens Above: Astronomical and Space Heritage, edited with John Campbell, and Nā Inoa Hōkū: Hawaiian and Polynesian Star Names, co-authored with Rubellite Kawena Johnson and John Kaipo Mahelona.

[Bart]

Caral, Peru: The oldest citadel in the Americas

16 March, 2007

LIP-jl) -- Using the Carbon 14 dating method, it has recently been established that Caral is the largest urban settlement with monumental architecture from the Late Archaic period in Peru. These results confirm that an advanced culture developed in the northern central area of the country, and that the Supe Valley was the center of the first state to be founded in Peru.

   The digs, performed since 1996, are witness of the importance of Caral in the Late Archaic Period.

   But the most surprising discovery so far has been that Caral is the oldest city in the Americas, having been built some 2627 BCE.

   Although it has been known for decades that monumental architectural remains exist in the Supe valley, nobody had ever taken the time to establish their precise age. The majority of archaeologists assumed that such buildings must have come from the formative period.

   That was also our working hypothesis in 1994, when we were prospecting in the lower and mid sections of the Supe valley, with financial help from the National Culture Institute (INC) and, later, the National Geographic Society. We studied the aerial photos of the area and the archaeological survey made by Carlos Williams and Francisco Merino.

   In 1996, when we began to excavate at Caral, our intention was to date the eighteen sites that bear common features and characterize the sociocultural expressions of their builders. We selected the area because it was one of the most extensive known sites and because it showed an ordered design with a variety of monumental architectural styles.

   Despite serious economic limitations, although we are being helped by the National University of San Marcos (UNMSM) and the municipalities of Supe Pueblo and Barranca, we continued with our excavations.

   In 2000, we sent samples away to be Carbon 14 dated. The results confirmed what we had already established using relative chronology in our first publications in 1997- namely that Caral is the most extensive urban site with monumental architecture from the Late Archaic period in Peru. This establishes that there was advanced cultural development in the central northern area of Peru and that the Supe valley was the centre where a State was founded for the first time in Peruvian history.

   An overview of Caral

Central northern development

   Not all the social groups that populated Peru in the Late Archaic period possessed the same level of development. The majority lived in sedentary villages and their principal activities were fishing, farming and herding.

   Two important technological innovations did occur, however, in the central northern area which increased productivity and contributed to population growth. They were the cotton fishing nets for use on the coast and the use of irrigation canals and the construction of small terraces for agriculture in the inter-Andean valleys.

   We now know that during the Late Archaic period Supe was a political state, and that its society was run by a permanently constituted authority with coercive-ideological power to support its decision making.

   We consider it a civilization because it was a society that produced a surplus, possessed stratified social classes, cities and state government.

   We class Caral as a city because it was built in an orderly manner and was populated by a large number of people who were involved in activities unrelated to food production such as government, religious observance, administration, manufacturing and commerce.

The Caral site

   Caral is located on the central northern coast of Peru, 182 kilometers from Lima and 23 kilometers from the coast, where the mid-section of the Supe valley begins at 350 metres above sea level.

   The city was constructed on an alluvial terrace, some 25 meters above the valley floor in a desert landscape crossed by Andean foothills and a few sand dunes. From within the city the valley is not visible, and only the sky, the mountains, and the magnificent work of man can be seen. The site must have been chosen for its natural features.

   The urban settlement occupies an area of 65 hectares, and consists of a central zone of monumental architecture, including both residential and non-residential buildings. The city?s nucleus comprises a series of 32 monumental structures arranged between depressions laid out in accordance with the residential complexes that surround them. Towards the valley, on the edge of the alluvial terrace, a group of small chambers can be distinguished. These were once an extensive residential area, removed from the public center.

   The eighteen settlements at Caral are a testimony to the sociopolitical importance of Supe. Distributed along both sides of the valley for a distance of some forty kilometers, Caral is one of the five most extensive settlements built within a ten square-kilometer radius.

   Around 2800 BCE, the population of Supe, distributed among a series of settlements both on the coast and in the valley, exhibited a strong degree of occupational differentiation.

   The coastal dwellers specialized in fishing and the extraction of mollusks and seaweed, while in the valley settlers opened up drainage canals to bring water down to their food crops and cotton fields.

The impact of its antiquity

   Until the Middle archaic period the individual members of society lived in equality, notwithstanding certain distinctions based on kinship, age and some non-hereditary personal qualities.

   The human remains from the period show similar levels of nutrition. From the beginning of the Late Archaic period, however, differences begin to appear among members of the same social group, which by this time had become hierarchical.

   At Caral, houses vary in location, size and building material. Some homes are located in the nucleus of the city, whereas others are more marginalized. Some are built from stone and consist of several rooms, although the majority were made from wattle and daub.

   The development of Caral is evidenced by these remains in the Supe Valley

   The eighteen radiocarbon dates obtained and published recently in Science Magazine, aroused great interest among the scientific community and the general public, principally because of the earliest date recorded (that of 2627 BC, at Caral.), the complex sociopolitical organization, and the advanced knowledge in the fields of science, technology, art and architecture in what has been established as the oldest city in the Americas, and comparable only with the great focuses of civilization in the Old World, in Mesopotamia, Egypt and India.

   In America, such results revive old questions regarding the conditions that made such early development possible in Peru.

   There is interest in the Peruvian process all around the world, a process that occurred in total isolation from other contemporary cultural centers, unlike the major centers of development in the Old World.

http://www.livinginperu.com/blogs/features/284

[Bart]

New Archaeological Findings On Political Power In Peru

Science Daily ? A team from the Universitat Aut?noma de Barcelona and the University of Almer?a has completed its second part of the "Proyecto La Puntilla", an archaeological expedition to the Peruvian province of Nazca, where last year it discovered a new type of construction. The latest findings show that a new political power based on the exercise of violence emerged on the south coast of Peru two thousand years ago. There was a State in which an aristocracy, based in Cahuachi, exercised its dominion on other, poorer communities in the Nazca Valley. The team has also observed practices such as cranial deformation.

   The excavations at the necropolis of El Trigal have uncovered new information on the repercussions of the emergence of the State in southern Peru. The archaeologists have found that El Trigal graves are very simple, in contrast with the extravagant tombs of the aristocracy around Nazca.

   The situation shows the poverty that existed among the community in El Trigal. The dominant group in the State of Cahuachi imposed the transfer of wealth through taxes and other means. This explains the poverty of those living in the area of La Puntilla.

   A settlement was established in El Trigal about 3000 years ago. Several centuries later, this had become an economically strong community with a vast network of relations with other territories. This hypothesis is backed up by the presence of valuable Spondylus shells (probably from the distant coasts of what today we know as Ecuador), obsidian (from the mountains), and craft tools, such as the boat decorated with the style known as Ocucaje 8 (possibly manual workers in the north).

   However, the necropolis excavated in El Trigal, dated as being from the first century AD, represents a later period of decline and pauperisation in the community, coinciding with the emergence of Cahuachi.
This data confirms that 1900 years ago a State existed in the Nazca Valley based in the monumental settlements of Cahuachi, where pyramids were built. Those governing Cahuachi belonged to one of the groups who shared control over the south coast of Peru, such as the aristocratic group described in the Paracas (near Pisco), in the same area.

   The dominant class in Cahuachi controlled the communities in the Nazca Valley using violence, forcing the communities to economically sustain the group in power. Between those communities were those that occupied the area known as La Puntilla, to the east of Nazca, where the research team has been excavating for the past two years.

Cranial deformation

   One of the key findings at the necropolis was that some of the bodies found in the tombs have undergone certain manipulations. One such manipulation was cranial deformation in order to obtain an "elongated skull", and this has been observed in one of the corpses.

   This practice took place during childhood by using wooden objects to put pressure on the skull. "Elongated skulls" are characteristic of the aristocracy buried in the tombs in Paracas, and a number of studies suggest that this treatment was a way of distinguishing dominant groups. This is why it is so significant that this characteristic has been found in an individual buried at the necropolis of a poor community in the Nazca Valley.
This discovery opens up a series of other questions: Is this the member of a family belonging to the dominant group? Or is the practice unrelated to a person's affiliation with a group? Was it a way of identifying individuals who took part in specific activities (for example, shamanism)?

   In another tomb, another interesting case has been found. Alongside the corpse of a woman, they have found the legs and feet of another individual. We know that decapitation and dismemberment were frequent among the first states of the region, so we cannot discard the possibility that this was an intentional act.
The fieldwork in this second part of the "Proyecto La Puntilla" ended in December, and the material and human remains uncovered are now being studied. The research will be amplified through a programme to analyse the DNA in order to find evidence on the affiliation of those individuals buried at the necropolis.

   The "Proyecto La Puntilla" is funded by the General Directorate for Fine Arts and Cultural Assets of the Spanish Ministry of Culture and by the Catalan Department of Education and Universities. The project is also recognised by the National Institute for Culture of Peru. The research team consists of archaeologists and students from Spain, Peru, Chile, Argentina, France and Italy.

Note: This story has been adapted from a news release issued by Universitat Autonoma de Barcelona.

http://www.sciencedaily.com/releases/2007/03/070322132951.htm

[Bart]

Peruvian Citadel Is Site Of Earliest Ancient Solar Observatory In The Americas



Science Daily ? Archeologists from Yale and the University of Leicester have identified an ancient solar observatory at Chankillo, Peru as the oldest in the Americas with alignments covering the entire solar year, according to an article in the March 2 issue of Science.

   Recorded accounts from the 16th century A.D. detail practices of state-regulated sun worship during Inca times, and related social and cosmological beliefs. These speak of towers being used to mark the rising or setting position of the sun at certain times in the year, but no trace of the towers has ever been found. This paper reports the earliest structures that support those writings.

   At Chankillo, not only were there towers marking the sun's position throughout the year, but they remain in place, and the site was constructed much earlier -- in approximately the 4th century B.C.

   "Archaeological research in Peru is constantly pushing back the origins of civilization in the Americas," said Ivan Ghezzi, a graduate student in the department of Anthropology at Yale University and lead author of the paper. "In this case, the 2,300 year old solar observatory at Chankillo is the earliest such structure identified and unlike all other sites contains alignments that cover the entire solar year. It predates the European conquests by 1,800 years and even precedes, by about 500 years, the monuments of similar purpose constructed by the Mayans in Central America."

   Chankillo is a large ceremonial center covering several square kilometers in the costal Peruvian desert. It was better known in the past for a heavily fortified hilltop structure with massive walls, restricted gates, and parapets. For many years, there has been a controversy as to whether this part of Chankillo was a fort or a ceremonial center. But the purpose of a 300meter long line of Thirteen Towers lying along a small hill nearby had remained a mystery..

   The new evidence now identifies it as a solar observatory. When viewed from two specially constructed observing points, the thirteen towers are strikingly visible on the horizon, resembling large prehistoric teeth. Around the observing points are spaces where artifacts indicate that ritual gatherings were held.
The current report offers strong evidence for an additional use of the site at Chankillo -- as a solar observatory. It is remarkable as the earliest known complete solar observatory in the Americas that defines all the major aspects of the solar year.

   "Focusing on the Andes and the Incan empire, we have known for decades from archeological artifacts and documents that they practiced what is called solar horizon astronomy, which uses the rising and setting positions of the sun in the horizon to determine the time of the year," said Ghezzi. "We knew that Inca practices of astronomy were very sophisticated and that they used buildings as a form of "landscape timekeeping" to mark the positions of the sun on key dates of the year, but we did not know that these practices were so old."

   According to archival texts, "sun pillars" standing on the horizon near Cusco were used to mark planting times and regulate seasonal observances, but have vanished and their precise location remains unknown. In this report, the model of Inca astronomy, based almost exclusively in the texts, is fleshed out with a wealth of archaeological and archaeo-astronomical evidence.

   Ghezzi was originally working at the site as a Yale graduate student conducting thesis work on ancient warfare in the region, with a focus on the fortress at the site.

   Noting the configuration of 13 monuments, in 2001, Ghezzi wondered about a proposed relationship to astronomy. "Since the 19th century there was speculation that the 13-tower array could be solar or lunar demarcation -- but no one followed up on it," Ghezzi said. "We were there. We had extraordinary support from the Peruvian Government, Earthwatch and Yale University. So we said, 'Let's study it while we are here!'"
To his great surprise, within hours they had measurements indicating that one tower aligned with the June solstice and another with the December solstice. But, it took several years of fieldwork to date the structures and demonstrate the intentionality of the alignments. In 2005, Ghezzi connected with co-author Clive Ruggles, a leading British authority on archeoastronomy. Ruggles was immediately impressed with the monument structures.

   "I am used to being disappointed when visiting places people claim to be ancient astronomical observatories." said Ruggles. "Since everything must point somewhere and there are a great many promising astronomical targets, the evidence -- when you look at it objectively -- turns out all too often to be completely unconvincing."

   "Chankillo, on the other hand, provided a complete set of horizon markers -- the Thirteen Towers -- and two unique and indisputable observation points," Ruggles said. "The fact that, as seen from these two points, the towers just span the solar rising and setting arcs provides the clearest possible indication that they were built specifically to facilitate sunrise and sunset observations throughout the seasonal year."

   What they found at Chankillo was much more than the archival records had indicated. "Chankillo reflects well-developed astronomical principles, which suggests the original forms of astronomy must be quite older," said Ghezzi, who is also the is Director of Archaeology of the National Institute of Culture in Lima, Peru.

   The researchers also knew that Inca astronomical practices in much later times were intimately linked to the political operations of the Inca king, who considered himself an offspring of the sun. Finding this observatory revealed a much older precursor where calendrical observances may well have helped to support the social and political hierarchy. They suggest that this is the earliest unequivocal evidence, not only in the Andes but in all the Americas, of a monument built to track the movement of the sun throughout the year as part of a cultural landscape.

   According to the authors, these monuments were statements about how the society was organized; about who had power, and who did not. The people who controlled these monuments "controlled" the movement of the sun. The authors pose that this knowledge could have been translated into the very powerful political and ideological statement, "See, I control the sun!"

   "This study brings a new significance to an old site," said Richard Burger, Chairman of Archeological Studies at Yale and Ghezzi's graduate mentor. "It is a wonderful discovery and an important milestone in Andean observations of this site that people have been arguing over for a hundred years."

   "Chankillo is one of the most exciting archaeoastronomical sites I have come across," said Ruggles. "It seems extraordinary that an ancient astronomical device as clear as this could have remained undiscovered for so long."

   Ghezzi is also a Lecturer in Archaeology at Pontificia Universidad Catolica del Peru in Lima, Peru. Support for the project came from Yale University, the Pontificia Universidad Cat?lica del Peru, the National Science Foundation, the Wenner-Gren Foundation, the Field Museum, the Schwerin Foundation, Earthwatch Institute and the Asociaci?n Cultural Peruano Brit?nica in Lima, Peru.

http://www.sciencedaily.com/releases/2007/03/070302082441.htm

[Bart]

Chankillo Observatory, Peru
Image copyright GeoEye/SIME

   About 400 kilometers (250 miles) north of Lima, Peru, lies an enigmatic, 2,300-year-old ruin named Chankillo. Archaeologists have nicknamed the ruin?s central complex the ?Norelco ruin? based on its resemblance to a modern electric shaver. The building?s true purpose long eluded them. Its thick walls and hilltop location suggested it was a fort, but why, researchers wondered, would anybody build a fort with so many gates and without a water source? Then in March 2007, two researchers, Ivan Ghezzi and Clive Ruggles, offered an explanation for the complex: at least part of it was a solar observatory.

   GeoEye?s IKONOS sensor captured this image of Chankillo on January 13, 2002, and this picture shows the features the archaeologists studied to infer the site?s purpose. The central complex appears in the upper left with its concentric rings of fortified walls. Southeast of the central complex are the Thirteen Towers, which vaguely resemble a slightly curved spine. On either side of the towers are observing points (little is left of the eastern observation structure), and south of the eastern observing point is another building complex, apparently used in part for food storage. Although the dark shapes in the northeast seem like rock outcrops, the higher-resolution image reveals they are probably trees.

   The Thirteen Towers were the key to the scientists conclusion that the site was a solar observatory. These regularly spaced towers line up along a hill, separated by about 5 meters (16 feet). The towers are easily seen from Chankillo?s central complex, but the views of these towers from the eastern and western observing points are especially illuminating. These viewpoints are situated so that, on the winter and summer solstices, the sunrises and sunsets line up with the towers at either end of the line. Other solar events, such as the rising and setting of the Sun at the mid-points between the solstices, were aligned with different towers.

   Why did the ancient inhabitants of this region cultivate such a thorough understanding of solar cycles? In addition to potential ceremonial purposes, the observatory may have had practical uses as well. In Peru's dry coastal reason, precipitation is seasonal, so a reliable solar calendar would help determine the optimal time to plant crops.

Further reading:

Mann, C. C. (2007). Mystery Towers in Peru Are an Ancient Solar Calendar. Science. 315: 1206-1207.
Ghezzi, I., and Ruggles, C. (2007). Chankillo: A 2300-Year-Old Solar Observatory in Coastal Peru. Science. 315: 1239-1243.

http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=17620

[Bart]

Kings Who Controlled the Sun

Pre-Incan rulers used a precise observatory to assert power

   For the last hundred years, travelers and explorers in Peru have puzzled over Chankillo, an ancient monument built on a remote desert hilltop 250 miles north of Lima. Dating from about 300 B.C., the ruins�three concentric stone walls that circle a fortress complex and 13 towers on a nearby hill�most likely were built by the Chavin, a pre-Incan civilization of llama tamers, farmers, and traders. Was the well-preserved complex used for military defense, religious ceremonies, or as a gathering place for the wealthy?

   By noting the alignment of the towers and their orientation to the sun�s location at sunrise and sunset, Catholic University of Peru archaeologist Ivan Ghezzi has finally solved the mystery: Together, the ruins form the oldest solar observatory in the Americas, he says. From a temple passageway, pre-Peruvians could watch the sun rise beyond the stone towers, which ranged from 6 to 20 feet in height and were spaced precisely to calibrate seasons, weeks, and days according to the changing position of the sun throughout the year.

   Such an observatory would have been an indispensable asset for an agricultural community, but the structure was probably more significant as a political tool than as a farmers� almanac. The Chavin�s ruling class, recognizing that knowledge is power, most likely built the towers to demonstrate their understanding of the sun�s behavior, Ghezzi concludes. By controlling these stone calendars, they appeared to control the sun itself�and thus maintained their power.

   �If keeping track of time had been the only concern, it could have been done in much simpler ways,� Ghezzi says. �Astronomy and the knowledge that comes with it�the ability to predict the movements of the sun�are things that can have political purposes.� Moreover, the observatory bears a striking resemblance to similar Andean structures still in use nearly 1,800 years later, suggesting that by the time the Incas inhabited this region of Peru, solar astronomy�and its political ramifications�were already ancient knowledge.

https://historyhuntersinternational.org/index.php?topic=1452.0