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    Re: Averaging
    From: Fred Hebard
    Date: 2004 Oct 23, 00:05 -0400

    Bill,
    
    Here is a graph of altitude versus time for meridian altitudes that
    vary from 15 to almost 90 degrees.
    
    The non-linearity is greatest in the graph for 75 degrees, and you can
    see that it's a pretty straight line by 50-75 minutes after passage.
    The non-linearity is less at 60 degrees but extends up to 100 minutes
    after passage.  By 45 degrees, the curve is almost imperceptible, but
    of course there (otherwise the sun could never rise or fall!).
    
    At meridian passages of 90 degrees you can see the sun goes straight
    up, then straight down; my mistake the other day was looking at that
    curve rather than one a bit lower, such as 75 degrees.
    
    These curves show the sun going down after meridian passage.  The
    curves for it going up before passage are mirror images extending to
    the left on the graph.
    
    Fred
    
    
    
    
    
    

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