On 7 November your 0830 zone time position was LAT 27°36.0'N, LONG 162°19.0'W. Your vessel was steaming on course 289°T at a speed of 19.0 knots. An observation of the Sun's lower limb was made at 0945 ZT. The chronometer read 08h 43m 11s and was slow 01m 51s. The observed altitude (Ho) was 38°21.1'. Local Apparent Noon (LAN) occurred at 1138 zone time. The observed altitude (Ho) was 45°35.0'. What was the longitude of your 1200 zone time running fix?

Question

Accepted Answer

Option A: 163°38.8'W. Calculate the longitude by running the 0830 fix forward to the time of the 0945 sight, then advance that line of position to 1200. Using the meridian altitude at 1138 to establish the latitude, the resulting 1200 longitude is 163°38.8'W, following standard Bowditch celestial navigation and running fix procedures.