Celestial Navigation · Fix — Two Bodies
A celestial fix from two bodies is strongest when the two bodies' azimuths differ by about:
- A5°
- B10°
- C180°
- D90°✓ Correct
Explanation
Two LOPs cross most sharply, giving the smallest error, when the bodies are about 90° apart in azimuth. Bodies close together (or 180° apart) in azimuth yield nearly parallel LOPs and a weak fix. For three bodies, about 120° apart is ideal.
Authority: Bowditch (Pub. No. 9), Selecting Bodies
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