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    Re: LOP by Sextant Box Shadow
    From: Hewitt Schlereth
    Date: 2008 Jul 18, 20:48 -0400

    Not really luck. This is the way Eratosthenes measured the
    circumference of the earth circa 200 BC. Instead of a sextant box he
    used a well in Syene, a camel, and an obelisk in Alexandria. Go to the
    head of the class.
    On 7/18/08, Greg Rudzinski  wrote:
    >      My sextant box was sitting before me on the dock casting a
    >  shadow.  Could this shadow provide me with a LOP?
    >  The answer is yes. The inverse tangent of the sextant box height
    >  divided by the length of the cast shadow generates an hs. I wasn't
    >  sure wether to treat this hs as an upper or lower limb so I just did
    >  the reduction as an upper limb to see what would happen.
    >  Latitude 34 09.8'N   Longitude 119 14.0'W   Height of eye at zero
    >  inverse tangent of (311.4mm/148.5mm) = 64 deg. 30.3' (hs)  at
    >  GMT(UTC,UT1) 21H 47M 28S on 07/11/2008
    >  Azimuth  248.9 true   Intercept 17.4' toward
    >    A very lucky LOP I think!
    >  >
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