Anticrepuscular Rays Over Khaşīl Dasht, Iran

May 31, 2017

Khasil Dasht2_Athmospheric_Anti_Clouds_Mountains (1)

Photographer: Amirreza Kamkar
Summary Authors: Amirreza Kamkar; Jim Foster

Sometimes nature surprises you. As I was traveling through northern Iran I decided to climb a foothill overlooking the village where I stopped for the day. I reached the top a little before sunset and suddenly a sea of clouds greeted me! As I was waiting for the Moon to rise, this amazing display of anticrepuscular rays quickly captured my attention. On this wide-field view, the western horizon is at far right and the eastern horizon at far left (where the rays converge). Since the sky above the western ridges appears to be cloud free it's likely that the rays result from sunlight (the Sun had just dipped below the horizon at my location) streaming through gaps in the mountains. The bright rays are made visible by dust and other aerosols in the air scattering the sunlight -- the dark lanes are simply areas where sunlight is blocked by the mountains. Note that crepuscular rays, though visible, are difficult to detect on this image. Photo taken on May 11, 2017.