Civil twilight occurs at 0558 zone time on 30... - USCG Navigation General

Civil twilight occurs at 0558 zone time on 30 December. Your DR position at that time is LAT 15°02'N, LONG 46°02'W. Which statement concerning the planets available for morning sights is TRUE?

A At 0558, Mars can be used for an ex-meridian observation.

B Venus will be visible low in the western sky.

C Saturn will be near the prime vertical.

D Venus, Jupiter, and Mars sights will yield a good three line fix.

AI Explanation

The correct answer is A) At 0558, Mars can be used for an ex-meridian observation. The explanation is as follows: 1. Confirm the correct answer: A) is the correct answer. 2. Explanation: At civil twilight, the sun is 6 degrees below the horizon, and several planets may be visible in the morning sky. Since the DR position is at LAT 15°02'N, LONG 46°02'W, Mars would be above the horizon and can be used for an ex-meridian observation at 0558 zone time on 30 December. 3. Explanation of why other options are incorrect: B) Venus will be below the horizon at this time. C) Saturn will not be near the prime vertical (due east or due west) at this time. D) While Venus, Jupiter, and Mars may be visible, they would not yield a good three-line fix since they are not in optimal positions for a morning sight.

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Question 507Navigation General

Civil twilight occurs at 0558 zone time on 30 December. Your DR position at that time is LAT 15°02'N, LONG 46°02'W. Which statement concerning the planets available for morning sights is TRUE?

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