On 2 April your 0900 zone time DR position is LAT 28°04.0'S, LONG 94°14.0'E. Your vessel is on course 316°T at a speed of 18.5 knots. What is the zone time of local apparent noon (LAN)?
• Local Apparent Noon (LAN) occurs when the Sun is on your local meridian, not necessarily at 1200 zone time • Relationship between longitude and time (4 minutes of time per degree of longitude) • How to compute meridian passage time from the Nautical Almanac for 2 April and adjust it for your longitude and vessel movement
• First, think about what time the Sun crosses your meridian at Greenwich on 2 April and how you get that for your longitude • Consider how your west‑going or east‑going course and speed between 0900 and LAN will change your longitude, and therefore slightly shift the LAN time • After estimating LAN in GMT/UT, carefully convert to the proper zone time for the time zone you are in
• Confirm whether your longitude is east or west and how that affects local time relative to Greenwich (later or earlier?) • Check the time zone you should be using for a longitude near 94°E (what whole‑hour offset from GMT fits that longitude range?) • Verify that you have allowed for the vessel’s change of longitude between 0900 and the estimated LAN time, and that your final answer is in zone time, not GMT/UT
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