Celestial Navigation · Intercept Method
In the altitude-intercept (Marcq St Hilaire) method, the intercept is the difference between the:
- AObserved altitude (Ho) and computed altitude (Hc)✓ Correct
- BSextant altitude and apparent altitude
- CGHA and LHA
- DLatitude and declination
Explanation
The intercept (a) is Ho minus Hc. If Ho is greater, the line of position is laid off toward the body; if less, away. The direction is the computed azimuth (Zn).
Authority: Bowditch, American Practical Navigator (Pub. No. 9), Sight Reduction
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