On 10 July your 0930 zone time DR position...

Question 1 of 2707066636eea28f7522a1c51a9c9

On 10 July your 0930 zone time DR position is LAT 26°31.0'S, LONG 4°41.0'E. Your vessel is on course 308°T at a speed of 22.0 knots. What is the zone time of local apparent noon (LAN)?

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Question 1 of 27070

On 10 July your 0930 zone time DR position is LAT 26°31.0'S, LONG 4°41.0'E. Your vessel is on course 308°T at a speed of 22.0 knots. What is the zone time of local apparent noon (LAN)?

🔍 Key Concepts

• Local Apparent Noon (LAN) occurs when the Sun is on your local meridian (crosses your longitude) • The relationship between Greenwich Hour Angle (GHA) of the Sun and your longitude at LAN • How to convert time = arc ÷ rate of GHA change (using 15° per hour as a base) into minutes of time

💭 Think About

• From your DR longitude at 0930, are you east or west of Greenwich, and does LAN occur before or after 1200 zone time for that longitude? • How many degrees (and minutes) of longitude must the Sun move in GHA from its 0930 value until GHA equals your longitude? Focus on that arc in longitude. • Once you find the arc, how many minutes of time does it represent at roughly 15° per hour, and what zone time does that add to (or subtract from) 0930?

✅ Before You Answer

• Be clear whether to add or subtract the travel time from 0930 to get LAN based on your longitude sign and the Sun’s motion. • Use the correct zone description (ZD) for LONG 4°41.0'E when relating Greenwich time to zone time. • Remember that LAN is when GHA (Sun) ≈ your longitude (taking east/west signs into account), not when it crosses 0° or 360°.