ON THE SOLAR CORONA PETROGLYPH IN THE CHACO CANYON

Abstract

Piedra del Sol is a free-standing rock in Chaco Canyon that marks June solstice sunrise. The petroglyph on the south face of Piedra del Sol in Chaco Canyon may depict the solar corona observed during the total solar eclipse of July 11, 1097 CE The southwest area of the rock contains features consisted with a sun watching station and faces December solstics sunset. During the 19th century, coronal mass ejection appears to have been observed during two total solar eclipses. The petroglyph on the south face appears to show a configuration of the solar corona that is consistent with a coronal mass ejection (CME). The hypothesis that a CME is depicted at Piedra del Sol is testable and can be disproven if the maximum of solar activity did not occur near 1097 CE. Recent studies indicate that 1097 CE was inded close to solar maximum. Miyahara et al. (2010) locate the maximum in 1098 CE based upon cosmogenic-isotopes. Vaquero and Trigo (2012) also found that 1098 CE was a maximum of solar cycle using a combination of documentary sources. The eclipse of 1097 CE occurred during a period of high solar activity, consistent with the interpretation of the petroglyph as a representation of solar corona during the solar eclipse of that year.