Island of Usedom Cloud Corona

January 03, 2006

Mega

Provided and copyright by: Reinhard Nitze
Summary authors & editors: Jim Foster; Reinhard Nitze

The comely cloud corona shown above was taken from the Isle of Usedom, Germany on September 17, 2005. Like all coronae, the cloud corona is a diffraction phenomenon, which results from the interference of sunlight (or moonlight) about water droplets. This one became visible briefly just before the approach of a mid morning thunderstorm. A characteristic of coronae is that their light is unpolarized, indicating that no reflections are involved. Coronae can be confused with rainbows, but bows result from the reflection and refraction of sunlight.

Photo details: Minolta Dimage Z1 camera, F-number - 8, exposure time - 1/1000 sec., ISO speed rating - 50, Focal length - 43.30 mm.

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