A subhelic arc is a rare halo, formed by internal reflection through ice crystals, that curves upwards from the horizon and touches the tricker arc above the anthelic point. Subhelic arcs are a result of ray entrance and exit through prism end faces with two intermediate internal reflections.
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“If I am not, may God put me there; and if I am, may God so keep me.”
—Joan Of Arc (c.1412–1431)