Sweden Rare Halos ~ A spectacular diamond dust display imaged by Lars-Göran Ljungquist at Falun on 15th December 2010.
© Lars-Göran Ljungquist , shown with permission.

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A 22° halo circles the low sun.   At each side there are dazzling bright sundogs. A parhelic circle sweeps through them and the sun itself.     A sun pillar reaches upwards to the 22° halo where it is topped by a ‘V’ shaped upper tangent arc.

 There the ‘everyday’ halos (if only they were) end. 

Light reflected from the outer faces of Parry oriented column crystals gives amazingly bright helic (old name heliac) arcs extending out from the sun.   

Parry crystals make themselves further evident in producing the second bright ‘V’ shaped halo, a sunvex Parry arc, above the upper tangent arc.    Further from the sun and touching an ‘ordinary’ supralateral arc there are rare Parry supralaterals.   At one time these were only seen in the ideal ice crystal regime of Antarctica but now crystals seeded by ski-slope snow machines sometimes produce them.

At left the image reveals a faint Wegener arc from a tortuous ray path through horizontal column crystals.   Below it, image enhancement helped a little by averted imagination hints at a trace of a subhelic arc.

An outstanding spectacle from ice crystals   aerodynamically oriented in just four ways.