On 22 May your 0437 DR position is LAT 25°18.5'N, LONG 51°18.0'W. You observe an unidentified star bearing 116°T at an observed altitude (Ho) of 11°27.8'. The chronometer reads 07h 40m 40s, and is 03m 24s fast. What star did you observe?

Correct Answer: Option A — Diphda

Convert chronometer time to GMT and determine GHA Aries. Calculate LHA for the DR position. Using the Sight Reduction Tables, compare the computed altitude and azimuth with the observed values. The parameters align with Diphda, matching the observed bearing of 116°T and altitude of 11°27.8'.