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Re: Az, Z, Zc and Zn - which one is what? How to use them properly?
From: David Pike
Date: 2017 Apr 13, 03:53 -0700
From: David Pike
Date: 2017 Apr 13, 03:53 -0700
In AP3270/HO249 Zn is the star’s azimuth. Z is the interior angle at the observer’s zenith of the PZX triangle. Z might or might not be the azimuth depending on the star’s LHA, and the observer’s hemisphere. Whether declination is the same as or contrary to the observer's latitude doesn’t seem to affect the rule.
N lat, LHA greater than 180° Zn=Z
N lat, LHA less than 180° Zn=360°-Z
S lat, LHA greater than 180° Zn=180°-Z
S lat, LHA less than 180° ZN=180°+Z
See diagrams. I’m not familiar with Az and Zc DaveP