Parry Kaleidoscope - Colourful low sun Parry and Upper Tangent arcs imaged by Jesper Gronne (Art of Nature site).   ©Jesper Gronne, shown with permission.
The upper arc is the sunvex Parry. The lower is a more common upper tangent arc.  At low sun both are 'V' shaped and close together. They merge when the sun is on the horizon.

Both are produced by horizontal column shaped ice crystals. The difference arises because Parry oriented crystals do not rotate about the long horizontal axis.

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