Question 1601Navigation General

70% to pass

The major problem with Moon sights is the _______________.

A augmentation effect caused by the relatively short distance to the Moon
B lack of a well defined limb during certain phases and positions in the sky
C approximations used in the solution caused by the variable horizontal parallax
D rapid changes in GHA and declination introduce errors into the calculations
AI Explanation

The correct answer is B) lack of a well defined limb during certain phases and positions in the sky. The major problem with Moon sights for the purpose of navigational fixes is that the Moon's limb (the visible edge of the Moon) is not always well-defined, especially during certain phases and positions in the sky. This can make it difficult to accurately determine the Moon's altitude, which is a critical measurement needed to calculate the navigator's position. The other answer choices are not the primary issue with Moon sights for navigational purposes.

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