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    Re: Latitude AND Longitude by Noon Sun
    From: George Huxtable
    Date: 2004 Jan 24, 00:56 +0000

    Frank Reed has described a method for determining the maximum altitude
    around noon. But what is needed for a simple calculation is the moment of
    local apparent noon (LAN). This is NOT the same as the moment of maximum
    altitude. The two are the same only when the vessel has no North or South
    component of velocity and when the Sun's declination is constant (at the
    He then, correctly, addressed the question of the Sun's changing
    declination, but ignored the (potentially much-greater) effects of the
    vessel's velocity.
    I suggest that it's important, even for a sailboat, to consider the effects
    of any North-South component of velocity on the time-difference between
    maximum Sun altitude and LAN. This was discussed in section 2 of my
    posting, of 23 Jan 2004, in the thread "Re: [NAV-L] Timed Noon sights for
    position". It's a matter that has otherwise been generally ignored in the
    recent discussions on this topic.
    contact George Huxtable by email at george@huxtable.u-net.com, by phone at
    01865 820222 (from outside UK, +44 1865 820222), or by mail at 1 Sandy
    Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.

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