On 17 November in DR position LAT 01°14.4'S, LONG 148°45.5'E, you take an ex-meridian observation of the planet Venus at upper transit. The chronometer time of the sight is 05h 31m 42s, and the chronometer error is 01m 50s fast. The sextant altitude (hs) is 64°41.1'. The index error is 1.8' off the arc, and your height of eye is 50 feet. What is the latitude at meridian transit?

Question

On 17 November in DR position LAT 01&deg;14.4'S, LONG 148&deg;45.5'E, you take an ex-meridian observation of the planet Venus at upper transit. The chronometer time of the sight is 05h 31m 42s, and the chronometer error is 01m 50s fast. The sextant altitude (hs) is 64&deg;41.1'. The index error is 1.8' off the arc, and your height of eye is 50 feet. What is the latitude at meridian transit?

Accepted Answer

Option C: LAT 01&deg;18.0'S. Convert chronometer time to GMT and extract Venus's geographical position from the Nautical Almanac. Correct the sextant altitude for index error and height of eye. Execute the ex-meridian computation outlined in Bowditch to derive the correct latitude at upper transit, LAT 01°18.0'S.