Heiligenschein

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File:Heiligenschein.jpg
Heiligenschein or hotspot around the shadow of a balloon on a field of standing crops, Oxfordshire.

Heiligenschein (German for ‘halo’ or ‘aureola’, literally ‘holy (or saintly) appearance’, pronounced [ˈhaɪlɪɡənˌʃaɪn]) (see also the article for halo, the optical phenomenon) is an optical phenomenon which creates a bright spot around the shadow of the viewer's head.

In photogrammetry and remote sensing it is more commonly known as the hotspot, and is due to the reduction in the proportion of shadows viewed at angles close to the backscatter direction. It may also be created when the surface on which the shadow falls has special optical characteristics. Both dry dusty surfaces and dewy grass are known to exhibit these characteristics. Nearly spherical dew droplets act as lenses to focus the light on the surface beneath them. Some of this light backscatters in the direction of the sunlight as it passes back through the dew droplet. This makes the antisolar point appear the brightest.

Heiligenschein around head of Buzz Aldrin's shadow due to extreme retroreflective properties of lunar regolith.[1] This is a close up of the reflection in Aldrin's visor, cropped from the famous image.[2] The white figure to the right is the photographer, Neil Armstrong.

The glory creates a similar halo effect by a different mechanism.

Cultural references

In the 2006 Scripps National Spelling Bee, this was the word which eliminated contestant Rajiv Tarigopula, who finished fourth for the second consecutive year.[3]

See also

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References