Question 1696Navigation General

70% to pass

The correction tables in the front of the Nautical Almanac for use with sun sights do NOT include the effects of _______________.

A mean refraction
B parallax
C semidiameter
D irradiation
AI Explanation

The correct answer is D) irradiation. The correction tables in the front of the Nautical Almanac for use with sun sights do not include the effects of irradiation. Irradiation is the apparent enlargement of the sun's disk due to the eye's response to bright light, and it is not accounted for in the standard correction tables. The tables do, however, include corrections for mean refraction (A), parallax (B), and semidiameter (C), which are necessary to accurately determine the sun's position for celestial navigation.

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