On 22 March your 0519 DR position is LAT 27°20.6'N, LONG 69°25.6'W. You observe an unidentified star bearing 115°T at an observed altitude (Ho) of 54°52.8'. The chronometer reads 10h 16m 47s, and is 02m 15s slow. What star did you observe?

Question

On 22 March your 0519 DR position is LAT 27&deg;20.6'N, LONG 69&deg;25.6'W. You observe an unidentified star bearing 115&deg;T at an observed altitude (Ho) of 54&deg;52.8'. The chronometer reads 10h 16m 47s, and is 02m 15s slow. What star did you observe?

Accepted Answer

Option A: Altair. Determine GMT by applying chronometer error to the reading. Extract GHA Aries and the star's SHA/Declination from the Nautical Almanac. Calculate the Local Hour Angle (LHA) and use the altitude-azimuth formula to compare the computed altitude and azimuth against the observed data, identifying the body as Altair.

On 22 March your 0519 DR position is LAT 27&deg;20.6'N, LONG 69&deg;25.6'W. You observe an unidentified star bearing 115&deg;T at an observed altitude (Ho) of 54&deg;52.8'. The chronometer reads 10h 16m 47s, and is 02m 15s slow. What star did you observe?

On 22 March your 0519 DR position is LAT 27°20.6'N, LONG 69°25.6'W. You observe an unidentified star bearing 115°T at an observed altitude (Ho) of 54°52.8'. The chronometer reads 10h 16m 47s, and is 02m 15s slow. What star did you observe?