Celestial Navigation · Great Circle
Pub. No. 229 sight reduction tables can also be used to compute great-circle distance and initial course because the math is identical to solving the:
- ASpherical (navigational) triangle✓ Correct
- BMercator sailing
- CPlane sailing
- DTraverse table
Explanation
The great-circle problem and the celestial altitude-azimuth problem both solve a spherical triangle. Entering Pub. 229 with the two latitudes and the difference of longitude yields distance (as altitude) and initial course (as azimuth).
Authority: Pub. No. 229; Bowditch (Pub. No. 9), great-circle sailing
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Related Celestial Navigation questions
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