Full 22 degree Halo

A large area of smooth cirrus produced this well defined 22 degree halo. There was no sign of tangent arcs so the ice crystals must have been very poorly oriented.

The reddish inner boundary of the halo is quite distinct and better defined than the whiter outer edge which blends into the sky background. The sky background just inside the halo is also noticeably darker than on the outside.

Forty minutes later the cirrus is more broken and the halo is less well defined.

Canon EOS 20D   4th June 2006   Composites of 2 images
Wiltshire, England

Other Halo Topics