Celestial Navigation · Latitude by Polaris
Latitude by Polaris is obtained by applying to the corrected sextant altitude of Polaris the:
- ADip only
- BEquation of time
- Ca0, a1, and a2 corrections from the Polaris tables✓ Correct
- DSemidiameter
Explanation
Latitude ≈ Ho − 1° + a0 + a1 + a2, where the three corrections (functions of LHA Aries, latitude, and month) reduce Polaris to the celestial pole. It gives latitude directly in northern latitudes.
Authority: The Nautical Almanac, Polaris (Pole Star) Tables
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