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    Almanac Moon Data
    From: Bill B
    Date: 2004 Oct 28, 17:01 -0500

    On page 4 of the almanac, there is a table of moon phases, with dates, and
    time in hours and minutes.
    
    On the daily pages the lower-right corner of the right-hand page has upper
    and lower meridian passage times, age in days, a percentage (of surface
    lighted?) and an image.
    
    I am not certain how the moon diagrams in the lower hand corner of the daily
    pages are correlated to time.
    
    My best guess is that the percentage-lighted figure is for 12:00 UT.
    
    I arrived at that by looking at moon phases and times on page 4, and picking
    several that were closest to 12:00 UT.  I chose those closest to 12:00 as
    the rate-of-change of percentage visible appears to be nonlinear compared to
    time, so I wanted to minimize that effect.  In the specific example of of
    first and last quarter I observed a 9-11% range-of-change per day, nominally
    .42 percent per hour.  Multiply that figure by the time difference between
    the time stated on table 4 and 12:00 the result agrees with the percentage
    figure in the daily pages.
    
    I have made the assumption that time stated for a phase on page 4 is the
    precise time (to the minute) when the moon is completely dark, 50%
    dark/light, and 100% light.  And assumptions often get me into trouble.
    
    Can anyone confirm or deny my assumptions regarding:
    1.  Page 4 moon phase table
    2.  What time the percentage figures on the daily page reference?
    
    Thank you,
    
    Bill
    
    
    

       
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