At 1845 zone time, on 17 March, while taking stars for an evening fix, you observe an unidentified star bearing 200°T at an observed altitude of 53°45.0'. Your DR position at the time of the sight is LAT 25°10.0'N, LONG 66°48.0'W. The chronometer time of the sight is 10h 47m 49s, and the chronometer error is 1m 54s fast. Your vessel is steaming on a course of 290°T at a speed of 18.0 knots. What star did you observe?
Official USCG Answer & Rule Citation
Correct Answer: Option A — Rigel
Adjust the DR position for the time elapsed between the 1845 ZT and the actual sight time. Calculate GMT, GHA, and LHA. Using the intercept method, the calculated altitude and azimuth for Rigel correspond to the observed data, confirming it as the correct celestial body for the fix.
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