Yesterday I posted one of the sunset shots I took in Iowa a few days ago. It was a nice, normal and beautiful image of the sun setting behind the clouds. Fine.
But after the sun actually set there was this shaft of sunlight that rose straight up from the horizon. It lasted about 15 minutes. The colors and clouds kept changing but the shaft stayed constant. You can see some of the color changes just in these three shots.
Does anyone know what causes this? The clouds were changing to rapidly to think that it was a break in the clouds somewhere over the horizon. There are no mountains in Iowa (duh), so why this shaft of light? It stayed in the same place, as I said, for 15 minutes.