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    Re: Using sun compass for calibrating boat compass
    From: Bill B
    Date: 2014 May 07, 20:11 -0400

    On 5/7/2014 7:21 PM, Sean C wrote:
    > In the previous post I mistyped the calculated azimuth as "88.2°". It
    > should've been 88.1°. Sorry
    I guess I can envision it in two ways.
    *My initial thought--Before meridian passage the object is moving
    diagonally from my vantage point, less vertical and more horizontal
    motion as it approaches meridian passage. Like the spoke of a wheel with
    one marker higher than another (N declination, N latitude) the outer
    marker would be north or east east of the inner marker (depending on
    time). Therefore its higher Ho apparent altitude vs Hc would shift its
    *That being said, when I am facing a celestial object refraction can
    only move it vertically along its meridian towards zenith. Therefore it
    is in fact where I see it along the horizontal axis.
    What I question in your examples are as follows:
    If declination, LHA and latitude remain constant can your theoretical
    body have two Hc's? One of the 3 variables would have to change for that
    to happen, and it becomes a whole different scenario.
    Thanks for serving as a sounding board.

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