photo #6146611

These anti-crepuscular rays were spotted by Samuel Uehara as the Sun was setting behind him in Cascavel, Paraná, Brazil. The subtle optical effect appears in the opposite direction from the Sun when it is low on the horizon. You can think of these beams as the opposite ends of the crepuscular rays sometimes seen fanning out from the Sun as it shines from behind clouds.The shadows Samuel spotted would have been cast right across the sky from behind him, where obstacles such as mountains or, more likely, clouds were off on the horizon. As they receded into the distance ahead, the lines of light and shade converge at the anti-solar point – in the exact opposite direction to that of the Sun. Behind the high-rises, the sky has begun to darken as the shadow of the Earth itself is cast up against its atmosphere. Above this horizontal shadow band, the brighter parts of the anti-crepuscular rays contain the rosy pink tones of the Belt of Venus, also known as the anti-twilight arch, caused by the atmosphere reflecting and scattering the evening rays back towards Samuel.