Greenwich Hour Angle, abbreviated GHA, is the angular measure of the celestial body from the Greenwich Meridian (also known as the Prime Meridian) along the celestial equator. Tabulated GHA is found in the daily pages of The Nautical Almanac. GHA Increment may be found in the yellow pages of The Nautical Almanac, under “Increments and Corrections.” SHA and v-correction applies to the stars, Moon or planets, and is covered in the Supplemental area.

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