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    Re: Compass correction using sunrise
    From: David Pike
    Date: 2022 Jun 30, 13:51 -0700

    Sorry

    All those cosine graphics wore me out.  My last message should have read:

    Frank Reed you wrote: In the tropics and assuming declinations in the Sun's range, the rising azimuth of a body is very nearly 90°-Dec (where Dec is signed), and the setting azimuth is nearly 270°+Dec.

     
    So, latitude zero, declination zero, azimuth at sunrise = 090°.  That figures.  It is also confirmed by the Amplitude Tables.  The difference between amplitude and declination gradually increases as declination and latitude increase although interestingly the percentage difference for a particular latitude stays about the same for any declination. E,g. at 23.5° declination and 23.5° latitude the difference is 2.3° or 9.8%. At 10 declination and 23.5° latitude it’s 0.95° or 9.5%.  I blame electronic calculators.  DaveP

       
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