On 22 March your 1834 ZT DR position is LAT 26°13.5' S, LONG 108°36.5' W. You observe an unidentified star bearing 077°T, at an observed altitude (Ho) of 43°10.5'. The chronometer reads 01h 32m 37s and is 01m 50s slow. What star did you observe?

Correct Answer: Option D — Alphard

Convert chronometer time to GMT, then apply the longitude to find LHA of Aries. Using the Sight Reduction Tables for Marine Navigation (Pub. 229), calculate the Local Hour Angle and Declination for the observed altitude and azimuth. Alphard matches the calculated coordinates for the given time and position.