Circumscribed Halo Over Nashua, New Hampshire
November 27, 2006
The photo above showing a circumscribed halo was taken at 12:30 p.m. (Eastern Standard Time) on October 6, 2006 from Nashua New Hampshire. This form of halo is tangent to the 22 degree halo at its upper and lower points. Near noon in early October, the Sun is approximately 42 degrees above the horizon at the latitude of Nashua. At this solar angle, the circumscribed halo may resemble a Parry Arc. Circumscribed halos change shape as the solar altitude varies.