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    Re: Sundog
    From: Bill B
    Date: 2013 Feb 16, 14:10 -0500

    On 2/16/2013 12:54 PM, Greg Rudzinski wrote:
    > After closer inspection of the image ......large snip....
    > Is there a UT time for the image ?
    
    Excuse my OCD. To solve a problem we first need to understand the
    problem. Frank stated:
    Lat 41d (Franks approx. location 41.5d N, 71.4d W)
    Hilly country ("Hilly" is relative. A hill in KS... ;-)
    YOU are facing the sundog
    YOUR sundog approx 5d high (using what as a horizon?)
    Sun blocked by hill to left
    Date February 10, (2013 assumed but not stated)
    
    Of importance Frank did not specify this is the sundog he saw, but
    rather the sundog YOU are facing. I think Frank's sundog was closer to
    41.5d N.
    
    To me this means MY sundog could be at any longitude I specify near
    sunset. Where I place myself determines time and therefore declination.
    For simplicity of calculations MY sundog was at 41d N and 75d W. (a bit
    north of Philadelphia, PA.) 41d N and not too far from Frank, and hilly.
    (A look at a topo map of Frank's immediate area does not suggest it is a
    natural for development of a downhill ski resort.)
    
    Once you set YOUR longitude and determine approx time (and declination)
    when observed CENTER of sun would be 5d above the horizon and adjust for
    dip, refraction and temp/pressure just plug 41d, adjusted HO/HC and
    declination into the sine formula for azimuth. Add 22d and voila.
    
    That's my take on the king's new cloths ;-)
    
    Bill B
    
    
    
    On 2/16/2013 12:54 PM, Greg Rudzinski wrote:
    > After closer inspection of the image ......large snip....
    > Is there a UT time for the image ?
    
    
    
    
    
    

       
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