At 1845 zone time, on 17 March, while taking stars for an evening fix, you observe an unidentified star bearing 200°T at an observed altitude of 53°45.0'. Your DR position at the time of the sight is LAT 25°10.0'N, LONG 66°48.0'W. The chronometer time of the sight is 10h 47m 49s, and the chronometer error is 1m 54s fast. Your vessel is steaming on a course of 290°T at a speed of 18.0 knots. What star did you observe?

Question

At 1845 zone time, on 17 March, while taking stars for an evening fix, you observe an unidentified star bearing 200&deg;T at an observed altitude of 53&deg;45.0'. Your DR position at the time of the sight is LAT 25&deg;10.0'N, LONG 66&deg;48.0'W. The chronometer time of the sight is 10h 47m 49s, and the chronometer error is 1m 54s fast. Your vessel is steaming on a course of 290&deg;T at a speed of 18.0 knots. What star did you observe?

Accepted Answer

Option C: Rigel. Calculate UTC and determine GHA Aries and SHA. Compute LHA and Declination for the star. By comparing these coordinates to the observed bearing of 200°T and altitude of 53°45.0', Rigel is identified. This follows standard celestial navigation procedures for star identification using the Nautical Almanac and DR position.