Celestial Navigation · Polaris
Latitude by Polaris is found from the observed altitude by:
- ASubtracting the declination of Polaris
- BAdding the equation of time
- CMultiplying Ho by the cosine of LHA
- DApplying the a0, a1, and a2 corrections from the Almanac and subtracting 1°✓ Correct
Explanation
Latitude = Ho − 1° + a0 + a1 + a2, where the three corrections come from the Polaris tables in the Nautical Almanac. Because Polaris lies very near the celestial pole, its corrected altitude approximates the observer's latitude.
Authority: Nautical Almanac
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