Celestial Navigation · Sight Reduction
A single celestial observation by itself provides:
- AA complete fix
- BLatitude only, in all cases
- CLongitude only, in all cases
- DOne line of position; at least two crossing LOPs are needed for a fix✓ Correct
Explanation
One sight yields one LOP — the vessel is somewhere on that line. Two or more LOPs from different bodies (or the same body at different times, advanced as a running fix) must cross to establish a fix.
Authority: Bowditch (Pub. No. 9)
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