Celestial Navigation · Polaris — Latitude
Polaris is observed with Ho = 40°00.0'. The almanac corrections are a0 = 1°02.4', a1 = 0.5', a2 = 0.3'. Using Latitude = Ho − 1° + a0 + a1 + a2, what is your latitude?
- A41°03.2'N
- B39°57.0'N
- C40°03.2'N✓ Correct
- D40°00.0'N
Explanation
Latitude = 40°00.0' − 1°00.0' + 1°02.4' + 0.5' + 0.3' = 40°00.0' + 3.2' = 40°03.2'N. The Polaris a0/a1/a2 corrections account for the star's small offset from the celestial pole.
Authority: Nautical Almanac, Polaris tables; Bowditch (Pub. No. 9), latitude by Polaris
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