On 25 February at 0622 ZT, you observe the upper limb of the Moon with a sextant altitude of 59°58.6'. Your DR position is LAT 30°28.3'S, LONG 102°39.3 E. The chronometer reading at the time of the sight is 11h 21m 18s and the chronometer is 48s slow. The height of eye is 59 feet and the index error is 2.5' on the arc. What are the azimuth (Zn) and intercept (a) of this sight using the assumed position?

Question

On 25 February at 0622 ZT, you observe the upper limb of the Moon with a sextant altitude of 59&deg;58.6'. Your DR position is LAT 30&deg;28.3'S, LONG 102&deg;39.3 E. The chronometer reading at the time of the sight is 11h 21m 18s and the chronometer is 48s slow. The height of eye is 59 feet and the index error is 2.5' on the arc. What are the azimuth (Zn) and intercept (a) of this sight using the assumed position?

Accepted Answer

Option A: Zn 305.4&deg;, a 4.2' T. Apply index error, dip, refraction, and semi-diameter to the observed altitude of the Moon. Calculate the LHA and declination using the Nautical Almanac. Solve the sight using the intercept method (Ho vs Hc) to determine the azimuth and intercept, resulting in Zn 305.4° and an intercept of 4.2' Toward.