Overhead a colourful circumzenithal arc is sculpted by hexagonal plate ice crystals drifting with their large faces nearly horizontal.
Almost touching it is a rare 46�halo from poorly oriented or cluster crystals. Why a 46° halo rather than the more common supralateral arc? In the top image the 22° halo made by the same crystals is bright and there is little sign of a tangent arc that heralds the column crystals necessary for a supralateral.
Circling closer to the sun is the familiar 22� halo guarded by sundogs and crossed by the parhelic circle.
Crystal populations changed for the all sky view at right. Horizontal column crystals had formed upper and lower tangent arcs and � near the horizon � infralateral arcs of widely separated colours. There is a hint also of a Parry arc.
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