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). For a more complete description, see the external link to "How are glories formed?"
20061217
Glory
A glory is an optical phenomenon produced by light backscattered (a combination of diffraction, reflection and refraction) towards its source by a cloud of uniformly-sized water droplets. A glory has multiple colored rings. 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. The phenomenon is also known as an anthelion (plural anthelia, from late Greek ανθηλιος, meaning "opposite the sun").
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). For a more complete description, see the external link to "How are glories formed?"
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). For a more complete description, see the external link to "How are glories formed?"
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