- Shadow bands
Shadow bands are thin wavy lines of alternating light and dark and can be seen moving and undulating in parallel on plain-coloured surfaces. [ [http://www.earthview.com/tutorial/effects.htm Effects During a Total Solar Eclipse ] ] Shadow bands are the result from the illumination of the atmosphere by the thin solar crescent a minute or so before and after totality. [ [http://www.williams.edu/Astronomy/IAU_eclipses/explanation.html Explanation from Barrie Jones, Open University ] ] However, a new theory has been put forward by Dr. Stuart Eves, who works for Surrey Satellite Technology Limited (SSTL), that shadow bands might actually be caused by infrasound, which involves the shadow of the moon travelling at supersonic speed which in turn produces high frequency sound that humans can't hear and because of this, creates a shockwave in front of the shadow, which causes shadow bands. Dr. Eves said "If proven, it would be a something of a revelation that eclipses are a sonic as well as an optical phenomenon." [ [http://news.bbc.co.uk/1/hi/sci/tech/7347180.stm ] ] In the 9th century (A.D.) shadow bands during a total
eclipse are described for the first time-in the Volospa, part of the old German poetic edda.Carl Wolfgang Benjamin Goldschmidt (Germany) calls attention to the shadow bands visible just before and after totality at some eclipses (based on the eclipse of
November 19 ,1816 ?) [ [http://www.mreclipse.com/Totality/TotalityApH.html Chronology of Discoveries about the Sun ] ] [ [http://www.mreclipse.com/Totality/TotalityApH.html Chronology of Discoveries about the Sun ] ]In 1842,
George B. Airy , the English astronomer royal, saw his first total eclipse of the sun and recalled shadow bands as one of the highlights. "As the totality approached, a strange fluctuation of light was seen upon the walls and the ground, so striking that in some places children ran after it and tried to catch it with their hands" [M.Littmann, K.Willcox, F.Espenak: Totality: eclipses of the sun 2nd edition. Oxford university press. page 119]References
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