On 25 June at 0612 zone time, morning stars were observed, and the vessel's position was determined to be LAT 28° 13.0' S, LONG 49° 34.0' E. Your vessel is steaming at 17.0 knots on a course of 066° T. A sextant observation of the Sun's lower limb is made at 1022 zone time. The chronometer reads 07h 19m 17s, and the sextant altitude is 35° 26.3'. The index error is 1.5' on the arc, and the chronometer error is 02m 51s slow. Your height of eye on the bridge is 58.0 feet. What is the azimuth (Zn) of this sight using the assumed position?
• Dead reckoning (DR) position advanced from the last fix to the time of the sight • How to get UTC of the sight from zone time, chronometer reading, and chronometer error • Using the Sun sight reduction (LHA, Dec, Lat) to determine the correct azimuth quadrant
• From 0612 to 1022, how far do you travel at 17.0 knots, and along what true course? Where does that put your assumed latitude and longitude? • Is the Sun, at 1022 local morning, likely to be generally in the NE, SE, SW, or NW quadrant from your DR position in the Southern Hemisphere? • Once you get an approximate bearing of the Sun from your position, which answer choices can you immediately rule out as being in the wrong quadrant?
• Be sure you convert zone time to UTC correctly, including the chronometer error sign (slow vs fast). • Confirm that your LHA of the Sun is in the correct range for a morning sight in the Eastern Hemisphere (less than or greater than 180°?). • Double‑check that your final Zn is in a quadrant that matches both the time of day (morning) and your latitude (South).
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