Antisolar Arcs

January 04, 2008


Provided by: Francesco De Comité
Summary authors & editors: Francesco De Comité, Jim Foster, Les Cowley

The photo above showing an impressive antisolar arc display was captured during a flight between Brussels, Belgium and Madrid, Spain. Antisolar arcs, directly opposite the sun and therefore below the horizon are rare. If you look carefully, you can see the shadow of the aircraft on the sub-parhelic circle (at the sub-anthelic point -- the darkened dot at the center of the photo). Click on photo to enlarge. The nearly horizontal arc is the subparhelic circle -- at the same elevation below the horizon as the Sun (and parhelic circle) is above it. Photo taken on August 7, 2006.