Truhin's pillars, however, are not the ordinary kind. Even two leading experts in atmospheric optics can't quite figure them out:
"These pillars are mysterious," say Les Cowley and Marko Riikonen. "They have unexplained curved tops and even curved arcs coming from their base.
Arcs in rare displays like these could be from column crystals to give parts of tangent arcs, others could be the enigmatic Moilanan arc or even the recently discovered reflected Parry arc. We do not know
– so take more photos on cold nights!"