Wednesday 8 April 2015

Sun dog in Wensleydale



I've posted about sun dogs before and here's another one. It's in the top picture, to the left of the Sun. They are caused by refraction - that's a reasonable guess given the splitting into colours. It's about hexagonal ice crystals in the high cirrostratus cloud - that's cirrus done as a thin layer. It's 22 degrees from the Sun to the sun dog. Outstretched arm with thumb and little finger deployed is 25 degrees. It's about right for a rough measurement. There's supposed to be another one on the opposite side of the Sun. The cloud was a bit thicker there but I convinced myself I could see something...