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    Re: Working Analemma
    From: Frank Reed CT
    Date: 2006 Nov 5, 19:31 EST
    Lu you wrote:
    "But the biggie is 30-foot tall analemma on the south wall of the main
    entry.  Sunlight enters through a skylight above and is focused by a
    reflecting mirror onto the wall (hence the location of the analemma on
    the south wall).  At noon every day, the spot of light is on the correct
    location for the day of the year on the analemma.  "
     
    One of the lecturers at the Seaport Planetarium at Mystic Seaport back in the late 70s painted an analemma on his living room ceiling. He had a mirror mounted on a little base on the windowsill of a south-facing window. Once a week at exactly noon local mean time, barring clouds, he would mark the spot on the ceiling where the Sun's image was projected by the mirror. After a year he filled in an arc connecting the points. Sure enough, he had that classic "figure eight" analemma shape (although as Herbert Prinz has explained, it probably shouldn't be called an analemma).
     
    -FER
    42.0N 87.7W, or 41.4N 72.1W.
    www.HistoricalAtlas.com/lunars

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