anthelion

anthelion
   The term anthelion comes from the Greek words anti (against, opposite to) and helios (Sun). It translates loosely as counter-Sun. The term is used in meteorology and astronomy to denote arare" physical illusion consisting of a diffuse, achromatic patch of light manifesting itself at the anthelion point, i.e. the spot on the horizon opposite the Sun, and at the same altitude as the Sun. It has been suggested that anthelia arise from the intersecting or overlapping of "anthelic arcs and/or related "halos, such as the parhelic circle, diffuse " anthelic arcs, and Tricker's and Wegener's anthelic arcs. But since they also occur in the absence of these halos, it has been suggested that the anthelion may deserve to be classified as a separate type of halo. As to the mediation of anthelia, various hypotheses exist. These revolve around the notion of ice crystals or ice prisms with a particular orientation present in cirrus clouds and the reflection of sunlight from either the inner or the outer surfaces of these crystals. In the past the term anthelion was used in a broader sense to denote a variety of physical illusions occurring at the side of the sky facing the Sun. Thus the French astronomer and author Nicolas Camille Flammarion (1842-1925) includes under the heading anthelia such phenomena as the "Brocken spectre and the "Ulloa circle.
   References
   Flammarion, C. (1873). The atmosphere.Trans-lated by Pitman, C.B. Edited by Glaisher, J. London: Sampson Low, Marston, Low, & Searle.
   Lynch, D.K., Schwartz, Pt. (1979). Origin of the anthelion. Journal of the Optical Society of America, 69, 383-386.
   Lynch, D.K., Livingston, W. (1995). Color and light in nature. Cambridge: Cambridge University Press.

Dictionary of Hallucinations. . 2010.

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  • anthelion — [ant hē′lē ən, an thē′lē ən] n. pl. anthelia [ant hē′lēə, an thē′lēə] or anthelions [ModL < Gr anthēlion < anti , against + hēlios, SUN1] a rarely seen, hazy white spot at the same altitude as the sun, but opposite in the sky, caused by a… …   English World dictionary

  • Anthelion — Ant*hel ion (?; 277, 106), n.; pl. {Anthelia}. [Pref. anti + Gr. ? sun.] (Meteor.) A halo opposite the sun, consisting of a colored ring or rings around the shadow of the spectator s own head, as projected on a cloud or on an opposite fog bank.… …   The Collaborative International Dictionary of English

  • Anthelion — An anthelion (plural anthelia, from late Greek ανθηλιος, opposite the sun ) is a rare optical phenomenon appearing on the parhelic circle opposite to the sun as a faint white halo, not unlike a sundog.How anthelions are formed is disputed. Walter …   Wikipedia

  • anthelion — Parhelion Par*hel ion, n.; pl. {Parhelia}. [L. parelion, Gr. ?, ?; para beside + ? the sun.] A mock sun appearing in the form of a bright light, sometimes near the sun, and tinged with colors like the rainbow, and sometimes opposite to the sun.… …   The Collaborative International Dictionary of English

  • anthelion — /ant hee lee euhn, an thee /, n., pl. anthelia / lee euh/. a luminous, white spot occasionally appearing at the sun s elevation but in the opposite part of the sky. [1660 70; < LGk anthélion, neut. of anthélios opposite the sun, equiv. to ant ANT …   Universalium

  • anthelion — noun A faint, white halo rarely seen in the sky opposite the sun on the parhelic circle …   Wiktionary

  • Anthelion — Ant|he|li|on das; s, Plur. ...lia u. ...lien [...i̯ən] (meist Plur.) <aus gleichbed. gr. anthe̅lion> Gegensonne (Astron.) …   Das große Fremdwörterbuch

  • anthelion — [ant hi:lɪən, an θi:l ] noun (plural anthelia lɪə) a luminous halo round a shadow projected by the sun on to a cloud or fog bank. ↘a parhelion seen opposite the sun in the sky. Origin C17: from Gk anthēlios opposite to the sun …   English new terms dictionary

  • anthelion — ant·he·li·on …   English syllables

  • anthelion — /æntˈhiliən/ (say ant heeleeuhn), /ænˈθi / (say an thee ) noun (plural anthelia /æntˈhiliə/ (say ant heeleeuh), /ænˈθiliə/ (say an theeleeuh)) (especially in polar regions) a luminous ring seen round the shadow of the observer s head as thrown by …  

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