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    Re: Side error and cylinders
    From: Bill B
    Date: 2015 Aug 28, 15:42 -0400

    On 8/28/2015 10:27 AM, Mark Coady wrote:
    
    Making you own brass cylinders. Nice. Legos are the poor man's
    alternative. Very consistent and few bucks for little set. I put a mic
    on the bunch, the lapped the winners down to the 0.0001.I had purchased
    the brass set, but they we way off. Ken offered to make it good, but by
    then a Purdue machinist friend had lapped them. The brass are great as I
    love shiny things but would not want them in my sextant box, especially
    on the water. The Legos are just what the doctor ordered if you want
    back up set on board" just in case."
    
    > P.S. can somebody please tell the full moon to come out in the daytime
    > this weekend, I want to try out my new higher magnification prism scope
    > on my lunar sun sights.
    
    Short answer: No, I for one cannot "...tell the full moon to come out in
    the daytime this weekend..." Well above my pay grade ;-)
    
    Not likely on planet Earth in mid or lower latitudes without divine
    intervention. Maybe some year above the arctic circle (or southern
    equivalent) near summer solstice when it is light all day, the moon's
    declination is high and in same hemisphere as the sun using an
    instrument that measures 180 + degrees. The moon is full because the Sun
    and Moon are on opposite sides of the earth, so full moon remains pretty
    much a night-time event.
    
    Kidding aside, the Nautical Almanac (NA) provides the time of local moon
    rise and set, local sun rise and set, and their meridian passages
    (based, if I recall, on Greenwich.) The time of the events adjusted for
    daylight saving time and the difference of your longitude from the
    nearest 15d meridian is accomplished in the normal manner for the sun.
    As the moon travels slower than the sun (which is why it shows up
    approximately an hour later every day) an adjustment must be made for
    that using Table II on page xxxii of the NA or via GHA and v in the
    daily tables.
    
    Sorry I couldn't assist in fulfilling your request. :-)
    
    
    
    

       
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