On 11 February your 1832 zone time DR position is LONG 110°52.6'W. At that time you observe Polaris with a sextant altitude (hs) of 26°19.8'. The chronometer time of the sight is 01h 34m 56s, and the chronometer error is 02m 16s fast. The index error is 2.7' off the arc, and the height of eye is 60.2 feet. What is your latitude by Polaris?

Question

On 11 February your 1832 zone time DR position is LONG 110&deg;52.6'W. At that time you observe Polaris with a sextant altitude (hs) of 26&deg;19.8'. The chronometer time of the sight is 01h 34m 56s, and the chronometer error is 02m 16s fast. The index error is 2.7' off the arc, and the height of eye is 60.2 feet. What is your latitude by Polaris?

Accepted Answer

Option A: 25&deg;27.2'N. Latitude by Polaris is determined by correcting the observed altitude for index error, dip, and refraction to find Ho. Applying the corrections (a0, a1, a2) from the Nautical Almanac based on LHA Aries yields the latitude. The calculation confirms 25°27.2'N as the correct position for the given parameters.