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    Re: shadow stick trivia question
    From: Byron Franklin
    Date: 2009 Oct 23, 12:38 -0700

     Using my star finder to see how the shadow works. The bearing of the
    body moves the shadow from point to point. the changing HT. causes the
    tip of the rod to throw a shadow, from the base according to the amout
    of change in body HT. Zenith Distance seems to be the controlling
    factor, the near by stars changed HT. quickly, so changed the HT. of
    the shadow more than the farther stars at the near my horizon. So
    summer would really change the shadow, winter would be straighter.
    Thats the way I saw the problem?
    
    On Oct 16, 7:15�am, Apache Runner  wrote:
    > Frank -
    >
    > You're right. � I realized the error I had in visualizing it. � A straight
    > line will have a shadow on the equinox that's due east/west. � It's tough to
    > visualize because at the moment of sunrise/sunset, the length of the shadow
    > is infinite, so it's really a limit. I really need to go calculate this.
    > Just for fun, I found the following applet:
    >
    > http://www.ies.co.jp/math/java/conics/hidokei/hidokei2.html
    >
    >
    >
    > On Thu, Oct 15, 2009 at 9:34 PM,  wrote:
    >
    > > Well, I'm never 100% sure, but I think that's right. The cone collapses to
    > > a plane for a great circle... a plane intersecting another plane (the local
    > > ground) yields a straight line.
    >
    > > -FER- Hide quoted text -
    >
    > - Show quoted text -
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