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   Circumscribed Halo - 43º high sun

Circumscribed Halo around a 43º high sun. Aurora photographer Tom Eklund (aurorae, halos and other images) captured this bright display in Finland on 11th May '02. The upper part of the circumscribed halo is visible, curving downwards over the fainter 22º halo and intercepting the parhelic circle at the sundogs. Incidentally, notice how at this solar altitude the sundogs no longer touch the 22º halo.
The matching HaloSim simulation shows the complete circumscribed halo. At solar altitudes below 50º only the upper and lower sections are particularly bright.

The bright parhelic circle was mostly formed by the same horizontal column crystals which formed the circumscribed halo. High sun circumscribed halos are often accompanied by a parhelic circle.