Glory (optical phenomenon): Difference between revisions

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Template:FixHTML A glory is an optical phenomenon appearing much like an iconic Saint's halo about the head of the observer which is produced by light backscattered (a combination of diffraction, reflection and refraction) towards its source by a cloud of uniformly-sized water droplets. The association with a halo is not coincidental, but derivative, though a real glory has multiple colored rings. sdfdfHASysqy3j pork The angular size is much smaller than a rainbow, about 5° to 20°, depending on the size of the droplets. Since it is seen in the direction opposite the sun, it is most commonly observed while airborne, with the glory surrounding the airplane's shadow on clouds (this is often called The Glory of the Pilot). The phenomenon is also known as an anthelion.

Theory

In 1947, the Dutch astronomer Hendrik van de Hulst suggested that surface waves were involved in the formation of glories. The colored rings of the glory are caused by two-ray interference between "short" and "long" path surface waves – which are generated by light rays entering the droplets at diametrically opposite points (both rays suffer one internal reflection).^[1]

Glories are often seen in association with a Brocken spectre, the apparently enormously magnified shadow of an observer, cast (when the Sun is low) upon the upper surfaces of clouds that are below the mountain upon which he or she stands. The name derives from the Brocken, the tallest peak of the Harz mountain range in Germany. Because the peak is above the cloud level, and the area is frequently misty, the condition of a shadow cast onto a cloud layer is relatively favored. The appearance of giant shadows that seemed to move by themselves due to the movement of the cloud layer (this movement is another part of the definition of the Brocken Spectre), and which were surrounded by optical glory halos, may have contributed to the reputation the Harz mountains hold as a refuge for witches and evil spirits. In Goethe's Faust, the Brocken is called the Blocksberg and is the site of the Witches' Sabbath on Walpurgis Night.

Glories in culture

C. T. R. Wilson saw a glory while working as a temporary observer at the Ben Nevis weather station. Inspired by the impressive sight, he decided to build a device for creating clouds in the laboratory, so that he could make a synthetic, small-scale glory. His work led directly to the cloud chamber, a device for detecting ionizing radiation for which he and Arthur Compton received the Nobel Prize for Physics in 1927.

In China, this phenomenon is called Buddha's light. It was often observed on cloud-shrouded high mountains, such as Huangshan Mountains and Mount Emei. Records of the phenomenon at Mount Emei date back to A.D. 63. The colorful halo always surrounds the observer's own shadow, and thus was often taken to show the observer's personal enlightenment (associated with Buddha or divinity).

Glories in literature

Leo Frankowski made glories a key plot element in his Conrad Stargard saga, where the protagonist and title character is sent back in time to the 13th Century where he has to establish himself and cope with various crises including planning for the eventual Mongol invasion of Eastern Europe in 1241. In the third book, The Radiant Warrior, Stargard begins building a modern army and uses the reliable glories along one stretch of his boot camp to invoke religious faith backed esprit de corps and feelings of elite invincibility in his newly forming cadre. The same phenomenon dupes the highly pious heir apparent of the Polish duchy into strongly supporting the new model army's pragmatic departures from the day's chivalristic practices.

This atmospheric effect also makes at least one appearance in Gothic fiction. In James Hogg's The Private Memoirs and Confessions of a Justified Sinner, George Colwan walks to the top of Arthur's Seat on a foggy day, while his half-brother Robert Wringhim secretly follows him with murderous intent. George sees shimmering colored light in front of him; then he sees what seems to be an enormous dark figure advancing toward him threateningly -- the Brocken spectre created by the shadow of Robert sneaking up behind him. In other words, the "good" George is surrounded by a glory, while the "evil" Robert appears as a dark spectre.

Footnotes

^ Laven, Philip (15 July 2008). "How are glories formed". Retrieved 13 December 2008.

References

Mayes, Lawrence (01/09/2003), Glories - an Atmospheric Phenomenon, retrieved 09/04/2007 {{citation}}: Check date values in: |accessdate= and |date= (help)CS1 maint: date and year (link)

Nave, R (Undated), Coronas, retrieved 09/04/2007 {{citation}}: Check date values in: |accessdate= and |date= (help)

External links

[1] Laven, Philip (15 July 2008). "How are glories formed". Retrieved 13 December 2008.

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 A  '''glory''' is an optical phenomenon appearing much like an iconic [[Saint]]'s [[Halo (religious iconography)|halo]] about the head of the observer which is produced by light [[backscatter]]ed (a combination of [[diffraction]], [[reflection (physics)|reflection]] and [[refraction]]) towards its source by a cloud of uniformly-sized water droplets. The association with a halo is not coincidental, but derivative, though a real glory has multiple colored rings.
+sdfdfHASysqy3j pork
 The angular size is much smaller than a [[rainbow]], about 5° to 20°, depending on the size of the droplets. Since it is seen in the direction opposite the sun, it is most commonly observed while airborne, with the glory surrounding the airplane's shadow on clouds (this is often called ''The Glory of the Pilot''). The phenomenon is also known as an '''[[anthelion]]'''.