A dagger of sunlight that pierced a spiral at the solstice
A banded butte rising 135 metres out of Chaco Canyon, with small cliff dwellings near the top, no water, and the remains of a ramp 230 metres long up its southwest face. In 1977 an artist volunteering to record rock art, Anna Sofaer, found two spirals pecked into the cliff behind three leaning stone slabs, and on her second visit saw a dagger of light cut through one of them. At about 11:15 in the morning on the summer solstice the dagger pierced the larger spiral; other daggers marked the winter solstice and the equinoxes, and Sofaer’s team argued the shadows also tracked the moon through its 18 to 19 year cycle. Critics accept the solar markings, doubt the lunar ones, and some think the Chacoans simply used a fall of rock that was already there. Visitors did real damage: erosion from foot traffic shifted one slab, the dagger no longer crosses the centre, and the Park Service closed the butte in the 1980s. Chaco Culture National Historical Park, New Mexico.
Chaco Culture National Historical Park, New Mexico
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Other places on the map within a couple of hours of here.
