On 23 September while taking stars for an evening fix, an unidentified star is observed bearing 261°T at an observed altitude of 61°35'. Your 1836 zone time DR position is LAT 25°18' S, LONG 162°36' E. The chronometer reads 07h 34m 12s, and the chronometer error is 01m 54s slow. Your vessel is steaming on a course of 230°T at a speed of 18 knots. What star did you observe?
Official USCG Answer & Rule Citation
Correct Answer: Option C — Antares
Determining an unknown star's identity requires calculating Local Hour Angle of Aries and Greenwich Hour Angle from chronometer time, then applying estimated latitude to find computed azimuth and altitude matching sight reductions.
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