Halos near Longview, Alberta Canada imaged by Cally Coman. Frozen Alberta extends to its skies for the halos tell us that there are low level "diamond dust" ice crystals in the air. The tall bright sundogs appear in front of the hills because the crystals forming them are closer. Tall sundogs are made by large plate shaped crystals wobbling and fluttering markedly in their downward drift (at some stage, tall pillars become difficult to separate from 22° halo fragments). Smaller plates are more aerodynamically stable and deliver squatter dogs. The same unsteady crystals made the upper and lower sun pillars and the parhelic circle passing faintly through the sun and extending more brightly beyond each sundog. ©2003 Cally Coman, reproduced with permission. |