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    Re: Polaris for Latitude- why so accurate?
    From: Bill B
    Date: 2014 Sep 27, 15:36 -0400

    On 9/27/2014 2:41 PM, Greg Rudzinski wrote:
    > Polaris changes altitude very slowly just like the Sun at or near LAN.
    Currently the declination of Polaris is 89°18.5'N. That means it is
    nominally 41.5' from the north pole. For most of the northern hemisphere
    it is circumpolar, meaning it never dips below the horizon.
    If you could view Polaris all day, twice a (sidereal) day it's Hc would
    be exactly  89°18.5'N. Once a day 89°18.5' minus 41.5', and once a day
    89°18.5' plus 41.5'. Azimuth wise, true north twice a day, and off to
    the east or west the remainder of the day. As Greg pointed out, that is
    a relatively slow rate of change.
    While it is great you are absorbing Bowditch, there is a table in the
    back of the NA (pages 274-276) that adjusts for the change in altitude
    and azimuth based on LHA Aries, month and latitude. No sight reduction
    required. The NA, one-stop shopping ;-)

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