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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Longterm Sun's GHA and Dec: what's under the hood?
From: Greg Rudzinski
Date: 2018 Dec 6, 13:30 -0800
From: Greg Rudzinski
Date: 2018 Dec 6, 13:30 -0800
Tony,
It is just a way to correct for the four year cycle of the Nautical Almanac and some small corrections due to aberration & nutation. Table 4a only needs to be worked with nearest whole hours to correct Orbit Time and Declination. Then just do a GHA table c.&d. look up to sum with the corrected Orbit Time for the correct GHA.
Greg Rudzinski