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    Re: Sextant observations in the Chesapeake Bay
    From: David Iwancio
    Date: 2022 Aug 1, 18:57 -0700

    For taking individual practice sights this seems reasonable (or it might be interesting to work "backwards" to determine the distance to land), but for a round of sights to get a celestial fix you'll end up with a (probably insignificant) bias towards the nearer shore.

    One question is how this error compares to how much dip varies in non-standard conditions.  One paper I found at https://journals.lib.unb.ca/index.php/ihr/article/view/27073 suggests that it can vary by as much as ~1.0' for a 2 °C difference between air and water temperature.

    On a side note, for Bowditch tables 12 & 14 the β0 term appears to be (1 - Re/Rr) where Re is the radius of the earth and Rr is the radius of curvature of a refracted ray of light.  I came to this conclusion from looking at https://www.mathscinotes.com/2013/08/distance-to-the-horizon-assuming-refraction/

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