Question 1668Navigation General

70% to pass

The navigator aboard a ship at approximately 165°E longitude observes the Sun at ZT 14-25-04 on 21 September. What is the GMT and Greenwich date of the observation?

A 03-25-04, 21 September
B 01-25-04, 21 September
C 02-25-04, 21 September
D 01-25-04, 20 September
AI Explanation

The correct answer is A) 03-25-04, 21 September. The key to determining the correct answer is to calculate the Greenwich Mean Time (GMT) of the observation, based on the given local time and longitude. Since the ship's location is at approximately 165°E longitude, the local time is ahead of GMT by 11 hours (165°E / 15° per hour = 11 hours). Therefore, the GMT of the observation is 03-25-04, which corresponds to 21 September. The other options are incorrect because they do not properly account for the time zone difference between the ship's location and GMT.

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Official Resources
USCG Navigation Rules (COLREGS) 33 CFR Navigation Rules USCG National Maritime Center
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