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    Landlubber Sunrise Table
    From: Joe Schultz
    Date: 2009 Oct 29, 04:25 -0700

    I don't really have a need for a nautical almanac or tide book when travelling 
    on land, but I do like to plan the trip to maximize daylight.  The attached 
    Sunrise Green Bay.pdf is built for the latitudes of "the lower 49" in the US, 
    and includes a worked example.
    
    First page is the table for 2010 (data from U.S. Naval Observatory website), 
    built in Microsoft Excel software.  Those who use tide books will recognize 
    the format.  Added the longitude table and minute-to-degree table at the 
    request of others.  I usually scribble the solution on this page, then erase 
    it before the next calculation.
    
    Second page was built out of frustration on my part.  It seems this 
    semi-graphical solution is the trick, as far as a beginner learning the 
    process.  Latitude and longitude degree scales are subdivided in 10min 
    intervals, and the F scale is subdivided in 0.02 intervals.  Pick the wrong 
    time zone meridian and the assumed longitude won't plot - self-correcting in 
    that respect.
    
    In the U.S., these two pages will print for 20 cents at a FedEx/Kinkos store.
     
    Third and fourth pages are a solved example, showing a lot of work that I do 
    on my fingers.  My solution is a minute off the U.S. Naval Observatory's 
    website solution.
    
    Question for the math wizards: is there a way to nomogram the latitude 
    correction directly from the linear F scale?  If so then I can eliminate the 
    multiplication boxes and reduce the graphical solution to addition and 
    subtraction.  Tried making the latitude scale logarithmic but it looks too 
    strange for the beginner.
    
    Critiques and ideas are welcome.
    
    Thanks,
    Joe
    
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