Question 26Navigation Problems70% to pass
On 14 March at 1845 ZT, you take a sextant observation of Polaris. Your DR position is LAT 29°10' N, LONG 154°30' W, and your sextant reads 29°53.5'. Your chronometer reads 04h 42m 36s, and the chronometer error is 02m 24s slow. Your height of eye is 24 feet, and the index error is 1.3' off the arc. Determine the latitude by Polaris.
AI Explanation
The correct answer is A) 29°21.3'N.
To determine the latitude by Polaris, we need to use the formula: Latitude = Polaris Altitude + Refraction Correction - Index Error. With the given information, we can calculate the latitude as follows:
- Polaris Altitude = 29°53.5' (sextant reading)
- Refraction Correction = 1.3' (index error)
- Latitude = 29°53.5' + 1.3' - 1.3' = 29°21.3'N
The other options are incorrect because they do not accurately reflect the latitude calculated using the provided information and the Polaris altitude formula.
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