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    Re: Interpolation to latitude
    From: Gary LaPook
    Date: 2009 Nov 13, 02:56 -0800

    The times of sunrise, etc., in the NA are for the LMT for the Greenwich 
    meridian and approximately correct for all other meridians. ( LMT at the 
    Greenwich meridian is the same as GMT.) To find the time at your 
    meridian you need only to convert your longitude to time (15� is one 
    hour, etc.) and combine that time difference with the time of the event 
    at the Greenwich meridian. If your watch is keeping zone time then the 
    values in the NA will be correct at the central meridian of the zone. In 
    this case you only need to correct the zone time for the difference 
    between your longitude and the longitude of the central meridian of the 
    time zone you are keeping, a maximum difference of thirty minutes.
    Young, Derrick CIV (USA) DeCA HQ PM wrote:
    > Joe,
    > I have been, quietly, following this discussion for a while.  
    > As far as I can tell, the only reason for the interpolation of the LAT
    > CORRN is to get the correction factors for the local sunrise/sunset
    > times as well as the nautical and civil twilight times.  This is because
    > the farther north/south of the equator you are, the more that the actual
    > N/C twilight and sunrise/set times are delayed/advanced from the zone
    > time meridian.
    > I believe that you want to know this so that you will know when to do a
    > sun rise/set sight.
    > I am probably wrong, and am constantly learning more.  So when Inuik
    > answers, I will learn some more.
    > Thanks for the clarification!
    > derrick
    > -----Original Message-----
    > From: navlist@fer3.com [mailto:navlist@fer3.com] On
    > Behalf Of joseph_schultz@rrv.net
    > Sent: Thursday, November 12, 2009 4:01 PM
    > To: NavList@fer3.com
    > Subject: [NavList 10601] Re: Interpolation to latitude
    > Hi George,
    > Sorry about the delay - was busy with the American Veteran's Day
    > holiday.  I'm going to answer in a 'round-a-bout way; the intent is to
    > not confuse Inuik.  This is his series of postings.
    > >
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