At 1622 ZT on 15 June, in DR position LAT...

Study

Question 1 of 2066636eea28f7522a1c51ab32

At 1622 ZT on 15 June, in DR position LAT 10° 15.2' N, LONG 135° 10' W, you observe an amplitude of the Moon. The center of the Moon is on the visible horizon, bearing 101.2° psc. The variation is 5° E. What is the deviation?

Back

Question 1 of 20

66636eea28f7522a1c51ab32

No comments yet

Be the first to share your thoughts!

If the question has a related picture, it will appear here.

🔍 Key Concepts

• Amplitude of a celestial body and how it relates to true bearing at the horizon • How to apply variation and deviation in the correct order when converting between compass and true bearings • Difference between psc (per ship’s compass), magnetic, and true bearings

💭 Think About

• From the DR latitude and date, think about whether the Moon’s true amplitude should be north or south of due east or west, and about how large that offset from 090°/270° is likely to be • Figure out how to get from the observed compass bearing (psc) to the true bearing of the Moon at the horizon using variation and deviation—what is the standard sequence of corrections? • Once you have an expected true bearing at the horizon and a corrected bearing from the compass, compare them: which way and by how much must the compass be in error?

✅ Before You Answer

• Be clear which way you apply variation 5° E: remember the correct rule relating True, Magnetic, and Compass (T–V–M–D–C) • Confirm the sign convention for deviation: is “east” deviation added or subtracted when going from magnetic to compass? • Check whether your final deviation sign (E or W) matches the direction that the compass reading must be moved to line up with the true bearing.

👋 Hi! I'm Genie, your AI study assistant. How can I help you with this question?

Quick actions

— No credit card needed