On 12 June your 1845 DR position is LAT 21°47'N, LONG 46°52'W when you observe a faint unidentifiable star through a break in the clouds. The star bears 019.0°T at a sextant altitude (hs) of 53°56.2'. The index error is 0.5' on the arc, and the height of eye is 45 feet. The chronometer reads 09h 43m 27s, and the chronometer error is 1m 46s slow. What star did you observe?

Question

Accepted Answer

Option A: Mizar. Determine GMT and LHA Aries. Calculate the star's GHA and Declination using the Nautical Almanac. By comparing the observed altitude and azimuth against the computed values for potential stars, Mizar is identified as the body that matches the sight reduction parameters for the given DR position and time.