On 13 September your 1830 ZT DR position was LAT 23°03'S, LONG 105°16'E when you observe a faint unidentifiable star through a hole in the clouds. The star bore 132.3°T at a sextant altitude (hs) of 29°34.6'. The chronometer read 11h 24m 39s and is 5m 08s slow. The index error is 1.0' off the arc, and the height of eye is 52 feet. What star did you observe?

Correct Answer: Option A — Beta Gruis

Correct the sextant altitude for index error, dip, and refraction to obtain Ho. Determine GMT and LHA. Using the sight reduction tables (Pub. 229), calculate the intercept and azimuth. The resulting position and bearing match the coordinates for Beta Gruis, confirming the star identification through standard reduction methods.