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  Geotimes - May 2007 - Peru's ancient solar observatory

Peru's ancient solar observatory

A line of 2,300-year-old stone towers north of Lima, Peru, known as the Thirteen Towers of Chankillo form what a team of archaeologists is saying is the oldest solar observatory in the Americas. The discovery that the line of stone markers tracks the sun’s progress across the sky also suggests that sophisticated sun worship may have thrived in the region nearly two millennia prior to the famous sun cults of the Incas, the team says.

Ranging from 2 to 6 meters high, the towers form a toothed horizon along a low ridge in north coastal Peru. The 4-square-kilometer ceremonial site also contains multiple structures and plazas, including two structures that precisely flank the towers to the east and west.

Archaeologists have known of the site since the 19th century, but rather than linking it to the path of the sun, researchers originally thought it tracked the moon’s movement. The new research, however, published March 2 in Science, suggests that the spread of the towers precisely follows the full range of movement of the sun at the June and December solstices, tracking its progress to within two to three days.

Margaret Putney
Geotimes contributing writer

For more about the solar observatory, read the original story posted online March 13, 2007, in the Geotimes Web Extra archive at:

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