Description: Tasks for navigation Task number: A1.1, A1.7 Topic: Celestial Navigation, Compass - Magnetic and Gyro Activ Determine compass error (magnetic and gyro) using azimuth choosing a suitable celestial body (Sun/ Stars/ Planets/ Moon). Apply variation to find the deviation of the magnetic compass. Minimum number of times that activity should be recorded: 6 (2 each phase) Sample calculation (Azimuth- Planets): On 06th May 2006 at 22h20m10s UTC, a vessel in position 48°00'N 050°00'E observed Mars bearing 327° by compass. Find the compass error. If variation was 4.0° East, calculate the deviation. GHA Mars (06d 22h): Increment (20m 10s): 089° 55.7 005° 02.5' v (0.9): (+) 00.3 GHA Mars: 094°58.5' Longitude (E): (+) 050 00.0' (plus-since longitude is easterly) LHA Mars: 144° 58.5 Declination (06d 22h): N 024° 18.6' d (0.2): (-) 00.1' Declination Mars: N 024° 18.5° P=144° 58.5' (If LHA<180°, P=LHA) A Tan Latitude/Tan P A Tan 48° 00 Tan 144° 58.5' A = 1.584646985 N (A is named opposite to latitude, except when hour angle is between 090° and 270°) B=Tan Declination/ Sin P B= Tan 024° 18.5'/ Sin 144° 58.5' B=0.787011353 N (B is always named same as declination) C = A+B = 2.371658338 N (C correction, A+/- B: If A and B have same name- add, If different name- subtract) Tan Azimuth=1/ (CX Cos Latitude) Tan Azimuth = 0.6301399 Azimuth = N 32.2° W (Azimuth takes combined name of C correction and Hour Angle- If LHA is between 0° and 180°, it is named "west", if LHA is between 180° and 360°, it is named "east") True Azimuth=327.8° Compass Azimuth=327.0° Compass Error=0.8° East Variation 4.0° East Deviation 3.2° West