Coast Guard Exams
Question 1771Navigation General70% to pass

When plotting a circle of equal altitude for a high altitude sight, the radius of the circle is determined by the formula _______________.

AI Explanation
The correct answer is B) 90° - Ho. The radius of the circle of equal altitude is determined by the formula 90° - Ho, where Ho is the observed altitude of the celestial body. This formula is derived from the fact that the circle of equal altitude is a small circle on the celestial sphere that is perpendicular to the observer's vertical circle. The radius of this circle is equal to the complement of the observed altitude (90° - Ho). The other options are incorrect because they do not accurately represent the formula for determining the radius of the circle of equal altitude.

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