Where’s the Sun?
December 29, 2017
Crepuscular rays are caused by cloud shadows cast on a hazy atmosphere. Dark rays are the shadows of the clouds, and bright rays are sunlight shining between clouds. The first picture shows a close up of a cloud and the edge of the shadow. If the sky were perfectly clear, the shadow would still be there but you couldn’t see it because there would be nothing to cast the shadow on (except air molecules, which would produce a very faint and probably undetectable shadow).
The second picture shows a wide angle shot of the same scene and the third illustrates the geometry, showing just how all the rays originate from the Sun. The rays are all parallel but perspective makes them appear to converge, just like railroad tracks converging to a point on the horizon. Photo taken with a Nikon Coolpix AW100 camera on September 6, 2014.