Rainbow Wheel Over North Central Illinois

March 13, 2011

Photographer: Claude Oesterreicher
Summary Author: Claude Oesterreicher; Jim Foster

The photo above shows anticrepuscular rays commingling with a portion of a rainbow as observed from north central Illinois. It was taken following a rain shower, a little before sundown, this past November (2010). The bright, nearly vertical, rainbow strip provides an interesting contrast with the horizontally laid out golds and browns of the autumn landscape. When a rainbow is interspersed with anticrepuscular rays, a rainbow wheel is formed. Both of these phenomena have the antisolar point as their focus, but they're not often observed at the same time. Whereas the rainbow is caused by refraction of sunlight in water drops, the rays result from clouds (on the opposite horizon) interfering with the passage of sunlight. Note also the supernumerary bows just inside the primary rainbow as well as the dim secondary bow at upper right.

Photo details: Camera Maker: FUJIFILM; Camera Model: FinePix E550; Focal Length: 7.2mm (35mm equivalent: 48mm); Aperture: f/4.5; Exposure Time: 0.0029 s (1/350); ISO equiv: 400; Exposure Bias: none; Metering Mode: Matrix; Exposure: program (Auto);White Balance: Auto; Flash Fired: No (enforced);Color Space: sRGB.