Wednesday, 29 July 2009
An impressive solar halo, created by ice crystals in cirrus clouds that refract the incoming sunlight, seen over a palm tree near the offices of the National Solar Observatory in Tucson, Arizona, on June 27, 2006.
--My thanks to Peter Marenfeld and NSO/AURA/NSF, for such a fantastic photo.
The 22-degree (radius) halo, caused by refraction of sunlight through the edges of six-sided ice crystals in high clouds, surrounds the Sun. It is always colored red on the inside, blue on the outside, as blue light refracts more than red.
The sky is darker inside the halo. The sky inside a rainbow is lighter. I would see a solar halo when I look towards the Sun. I would only see a rainbow with the Sun behind me. It is said that a true rainbow is really a circle. A rainbow is violet in the inside and red on the outside. It's like the halo and the rainbow are polar opposites or something.
Photo of Rainbows and heavy rain over Sointula on Malcolm Island, Northern Vancouver island.
--My thanks to Rolf Hicker for this fabulous, vibrant shot.