On 2 January your 1759 zone time DR longitude is 45°17.6' W. At that time you observe Polaris with a sextant altitude (hs) of 24°16.5'. The chronometer time of the sight is 08h 57m 10s, and the chronometer error is 02m 16s slow. The index error is 3.5' on the arc, and the height of eye is 42.5 feet. What is your latitude by Polaris?

Question

On 2 January your 1759 zone time DR longitude is 45&deg;17.6' W. At that time you observe Polaris with a sextant altitude (hs) of 24&deg;16.5'. The chronometer time of the sight is 08h 57m 10s, and the chronometer error is 02m 16s slow. The index error is 3.5' on the arc, and the height of eye is 42.5 feet. What is your latitude by Polaris?

Accepted Answer

Option B: 23&deg;18.8'N. Correct the sextant altitude for index error, dip, and refraction. Determine the LHA of Aries using the chronometer time and DR longitude. Apply the Polaris correction factors (a0, a1, a2) from the Nautical Almanac to the altitude to calculate the latitude, yielding the correct value of 23°18.8'N.