figureposted on 03.01.2012, 00:00 by Christopher Davis
This photo was taken under Painel do Pilão, a rock art site near Monte Alegre, along the Amazon River in Brazil. The image is a 22° sun halo that is formed when sunlight is refracted by ice crystals in the Earth’s upper atmosphere. My research focuses on rock art in this region, which features numerous images of concentric circles. For a long time this concentric imagery has been explained by local inhabitants as representing the sun and the moon. The circles are usually red, but sometimes they have alternating red and yellow bands. I believe these concentric circles in the rock art represent the sun halo phenomenon that occurs often for both the sun and the moon during the rainy/flood season along the Amazon River. The rock art, which is believed to be thousands of years old, probably marked the meteorological phenomenon as the “sign” of the returning wet season, and the renewal or abundance it brings.