Question 29Navigation Problems
70% to passOn 12 March your 1846 zone time DR position is LONG 129°16.5' W. At that time you observe Polaris with a sextant altitude (hs) of 28°01.5'. The chronometer time of the sight is 03h 44m 10s, and the chronometer error is 01m 55s slow. The index error is 2.2' off the arc, and the height of eye is 59.8 feet (18.2 m). What is your latitude by Polaris?
The correct answer is D) 27°33.7'N. To calculate the latitude by Polaris, we need to use the formula: Latitude = Polaris altitude + Polaris correction. The Polaris correction is a function of the longitude and the time of the observation. Given the information provided: - Polaris altitude (hs) = 28°01.5' - Chronometer time = 03h 44m 10s - Chronometer error = 01m 55s slow - Index error = 2.2' off the arc - Height of eye = 59.8 feet (18.2 m) - Longitude = 129°16.5'W Using these values and the appropriate formulas, the calculated latitude is 27°33.7'N, which corresponds to answer choice D. The other answer choices are incorrect because they do not match the calculated latitude based on the given information and the relevant formulas and procedures for determining latitude by Polaris observation.
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