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Archaeoastronomy & Ethnoastronomy News


Number 17 September Equinox 1995

by D S P Dearborn

Once again, I have returned from wandering around the altiplano with a compass in one hand, and a cerveza in the other. When I listen to guides at Machu Picchu make fantastic assertions about the use of the Intihuatana stone as an observatory, or watch visitors to the Island of the Sun walk past the sacred rock, birthplace of the sun, to photograph the nearby pile of well-polished andesite blocks that some locals arranged as a table, I sense the continuing opportunities for studying Andean astronomy (and walking around the altiplano). It also makes me think about the types of observations made by the Inca. As a result, this quarter's essay is a consideration of the significance of different types of celestial observations,

Early ethnohistoric accounts of Peru describe the activities of skywatchers who measured the way light entered a window, or watched how it fell on a wall (or possibly from a wall). These individuals (called yanca in the Huarochiri manuscript) were local specialists who monitored the motion of the sun. From this light and shadow watching, dates were obtained for plantings, harvests, and festivals. The scheduling of such activities is important for coordinating and organizing a group, forming a society .

A very different type of observation is described by an anonymous chronicler, in the Discurso de la sucesin y gobierno de los Yngas [ca 1570]. He writes of the Inca festival that began the planting season. Sometime in the month of August, the Inca gathered around the usno, a stone in the plaza of Haucaypata, to watch the sun set between two pillars on a nearby hill. He states that these pillars were 50 paces (a pace consisted of two steps, so approximately 70 meters) apart. At the distance of Picchu, the hill over which the sun sets in August, such pillars would appear to have a separation of over 2o. This is much too wide for a precise date determination. However, the beginning of the planting season does not require a starting date of a particular day. This large separation also permitted most of people gathered in Haucaypata to witness the observation, along with the ruling Inca. Perhaps this group participation was more important than determining a particular date. Such activities provided an annual confirmation of the ruling Inca's position as the intermediary to the sun, the deity with the power to make things grow.

The basic nature of these observations is distinctly different. One involves monitoring celestial objects in a systematic way, an activity that can be identified with the modern practice of science. The other utilizes the commonly accepted power of a natural force (the sun god) in a ceremony that helped organize a complex society. The contrast between these two observations leads to some general questions that might be asked of any suggested alignment.

Presuming an alignment to be intentional (a separate and already well- recognized issue), one might ask who used it, a specialist, the ruler, or the general populace? Why was this observation made, for monitoring celestial motions in a systematic way, or as an activity organizing a group? How was it employed; did someone really press his nose against a major building to peer along the wall to see a particular sunrise? We can not look into the mind of a long-dead astronomer, but the nature of a site frequently provides some information. Was it located in a public area, or a place with restricted access? How many people could participate in the observation?

Because naked eye observations can be accurately performed in a small area with perishable equipment, true observatories, the places where specialists monitored the sky, may be very difficult to find. . Nevertheless, the large public structures or monuments that (intentionally) display astronomical phenomena argue that those skilled specialist must have existed with their places of work. The public monument and the astronomers' observatory provide different information on the people who used them. The expenditure of resources to build the a public structure gives a measure of the pracitcal value that a society found in astronomy. Access to the actual observatory suggests whether or not there were restrictions on this type of knowledge.

The examples offered here do not exhaust the range of ways in which astronomy has been integrated into society, and this integration of astronomy with human activities is not restricted to the past. A recent book by Baile Oakes, Sculpting with the Environment - A Natural Dialogue (Van Nostrand Reinholt Press, 1995) contains a number of examples where modern art and architecture were designed to work with the sky. Cautious consideration of the questions posed here may convert an alignment from an interesting datum, to an indicator of the organization and interests of a society.

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