On 10 March in DR position LAT 21°42.0'S, LONG 57°28.0'E, you take an ex-meridian observation of the Sun's lower limb. The chronometer time of the sight is 08h 28m 17s, and the chronometer error is 00m 00s. The sextant altitude (hs) is 72°08.0'. The index error is 3.4' on the arc, and your height of eye is 52.7 feet. What is the latitude at meridian transit?

Question

On 10 March in DR position LAT 21&deg;42.0'S, LONG 57&deg;28.0'E, you take an ex-meridian observation of the Sun's lower limb. The chronometer time of the sight is 08h 28m 17s, and the chronometer error is 00m 00s. The sextant altitude (hs) is 72&deg;08.0'. The index error is 3.4' on the arc, and your height of eye is 52.7 feet. What is the latitude at meridian transit?

Accepted Answer

Option C: LAT 21&deg;45.5'S. Calculate the latitude at meridian transit using the ex-meridian observation method. Correct the sextant altitude for index error, dip, and refraction to find the true altitude. Applying the reduction to the meridian, the resulting latitude is 21 degrees 45.5 minutes South, consistent with the celestial observation.