Celestial Navigation · Polaris
Polaris can be used for a latitude sight:
- AOnly in the Northern Hemisphere, where its altitude approximates the latitude✓ Correct
- BOnly in the Southern Hemisphere
- CAt any latitude, including the equator at all times
- DOnly at local apparent noon
Explanation
Polaris is near the north celestial pole, so it is visible only from the Northern Hemisphere and sits too low near the equator to observe reliably. Its corrected altitude is approximately equal to the observer's latitude.
Authority: Bowditch (Pub. No. 9)
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