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    Re: lat/long from meridian passage
    From: Gary LaPook
    Date: 2011 Jan 25, 22:47 -0800
    A simple way to deal with the changing declination for determining LAN is to adjust your course to account for the movement of the sun. The sun changes declination fastest around the equinoxes and then it is only at the rate of one knot north or south. Right now the sun is moving north at a rate of 0.2 knots. If your ship, Jeremy, is making 18 knots, even at the equinox you only have to change your course by three degrees so that it will have a vector to the north (or south) of one knot and hold it for a half hour around the estimated time of LAN and this will put you one-half mile off course and add almost zero additional miles to a trans-ocean passage. If you were to do it today you would only have to change course 0.6 degrees to the north which will put you only 0.1 nm off course after a half hour.

    The above applies if your original course was due
       
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