Celestial Navigation · Altitude Definitions
Observed altitude (Ho) is best described as the:
- ARaw reading off the sextant arc
- BAltitude assumed for the table entry
- CAltitude of the visible horizon
- DFully corrected altitude of the body's center above the celestial horizon✓ Correct
Explanation
Ho is the sextant altitude after all corrections (index, dip, refraction, semidiameter, parallax), referred to the body's center and the celestial horizon. It is compared with Hc to get the intercept.
Authority: Bowditch (Pub. No. 9), altitude corrections
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