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    Re: Sign of d in HO249
    From: David Iwancio
    Date: 2020 Apr 24, 19:20 -0700

    DaveP:

    Take a look at the azimuths for the body.  The higher declination body is on the "inside track" around the pole and starts its turn before the lower declination body, so at the hour angles you're looking at the differences in azimuth will be increasing.

    For the moment, I'd suggest meditating upon Bowditch table 20:  "Meridian Angle and Altitude of a Body on the Prime Vertical Circle."  For declinations greater than latitude, it tabulates the hour angle and altitude of when the star is moving strictly vertically (i.e. where the "d" for azimuth values would change sign.)

       
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