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Baltic Halos ~ A wintry scene at Tallinn, Estonia by Isaac Pascual (Isaac GP Photography).

The specks are glints from individual diamond dust crystals.

Notable is the halo directly beneath the circumzenithal arc at top. It is a 46° halo rather than a supralateral arc. One way to distinguish between the two is that supralaterals always touch the CZA whereas the 46° halo is sometimes separate.

All images ©Isaac GP Photograph, shown with permission

Supralateral arcs and the 46° halo cannot always be distinguished by a separation from the CZA. The distance is too small at sun heights between 15 and 27°. Look whether the outer halo has a cusp where it crosses the parhelic circle. No cusp = 46° halo. Look at the intensity of the upper tangent arc – a weak UTA hints at insufficient column crystals to generate a supralateral. Conversely, a bright outer arc and weak 22° halo says supralateral. More signs here.

Upper and lower sun pillars and the parhelic circle form a cross centred on the sun.

Formation of the glitter path in the sea is not that far removed from the mode of creation of the sun pillars. In both cases, slightly tilted mirror surfaces are responsible.

Distance between CZA
        and 46° halo