Celestial Navigation · Latitude by Polaris — Corrections
The a0, a1, and a2 corrections in the Polaris tables depend, respectively, on:
- AThe sun's declination, dip, and refraction
- BLHA of Aries, the observer's latitude, and the month✓ Correct
- CThe chronometer rate
- DThe vessel's speed
Explanation
Latitude = Ho(Polaris) − 1° + a0 + a1 + a2, where a0 is taken with LHA Aries, a1 with latitude, and a2 with the month. The three small corrections account for Polaris's slight offset from the exact pole at the time of observation.
Authority: Nautical Almanac, Polaris Tables
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