29 January 2025
Clear skies and skinny icy clouds have made this an amazing week for solar canine and 22 diploma halos within the sky. I’ve seen each close to sundown this week: Final Sunday at Schenley Park golf course and yesterday at Duck Hole.
Solar canine are vivid rainbow spots to the left and proper of the solar …
… generally attributable to the refraction and scattering of sunshine from horizontally oriented plate-shaped hexagonal ice crystals both suspended in excessive and chilly cirrus or cirrostratus clouds, or drifting in freezing moist air at low ranges as diamond mud. The crystals act as prisms, bending the sunshine rays passing via them with a minimal deflection of twenty-two°.
Typically you see just one.
Final Sunday two solar canine had been linked by a 22 diploma halo, a faint rainbow attributable to the identical atmospheric situations as solar canine.
If you happen to’re actually fortunate you’ll additionally see a circumzenithal arc, an the wrong way up rainbow on the high of the halo. I used to be lucky to see all three on 5 Nov 2022 at Yellow Creek State Park.
I haven’t seen all three this week … but. The very best time is throughout the hour earlier than sundown.