Question 60Navigation Problems70% to pass
On 3 December evening twilight for your vessel will occur at 1901 zone time. Your vessel's DR position will be LAT 24°18.5' S, LONG 110°30.6' W. Considering their magnitude and location, what are the three stars best suited to observe for a fix at star time?
AI Explanation
The correct answer is C) Alpheratz, Achernar, Nunki.
The key factors to consider are the vessel's location (LAT 24°18.5' S, LONG 110°30.6' W) and the time of star observation (evening twilight at 1901 zone time). Based on the star charts and tables used for celestial navigation, the three stars best suited for a fix at this location and time are Alpheratz, Achernar, and Nunki. These stars are relatively bright, well-positioned in the sky for evening twilight observations, and provide a good geometric spread for obtaining an accurate celestial fix.
The other answer choices, while containing suitable navigation stars, are not the optimal trio for the given scenario based on the star's relative positions and brightness at the specified time and location.
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