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Halo over Santiago de Compostela, Spain imaged by Jonathan Shock. ©Jonathan Shock, shown with permission.

22° halo or circumscribed halo? When the sun is high the circumscribed halo is almost circular and not easy to distinguish from the 22°. It has brighter colours and is sharper but otherwise is very similar.

The sun was 61° high** when this halo was seen at 14:20 local time on April 27th. At that altitude a circumscribed bow would be distinctly oval. This is a 22° halo. Another clue to its identity is the slow fall off in the bright white halo brightness outside the 22° circle.

**Solar elevation can be calculated with this tool.