On 11 May in DR position LAT 28°13.7'N, LONG 168°36.3'E, you observe an amplitude of the Sun. The Sun's center is on the celestial horizon and bears 283°psc. The chronometer reads 07h 13m 19s and is 02m 56s slow. Variation in the area is 13°E. What is the deviation of the standard magnetic compass?

Question

On 11 May in DR position LAT 28&deg;13.7'N, LONG 168&deg;36.3'E, you observe an amplitude of the Sun. The Sun's center is on the celestial horizon and bears 283&deg;psc. The chronometer reads 07h 13m 19s and is 02m 56s slow. Variation in the area is 13&deg;E. What is the deviation of the standard magnetic compass?

Accepted Answer

Option B: 5.6&deg;W. Calculate the Sun's declination and the observer's latitude to find the true amplitude using the formula sin(Amp) = sin(Dec) / cos(Lat). Compare the true amplitude to the compass amplitude (psc) to determine compass error. Applying variation (13 degrees E) to the compass error yields a deviation of 5.6 degrees West.