Lab Polaris Observation for AzimuthObjective:This lab will familiarize the student with procedures for determining the true azimuth of a survey line by star observations. Overview:The horizontal angle from a star such as Polaris ( the North star) is measured at a known instant of time to a survey mark. From the measured time of observation, the azimuth of Polaris may be computed by spherical trigonometry. The survey mark's true azimuth is computed by combining the star's true azimuth with the measured angle,Field Procedures. Calculations, and Analysis:1.Measurements: In the field, find a station with a clear view of the northern sky. Set or choose a distinct point for the instrument setup. Set or choose a survey mark about 300 ft away from the instrument. Calibrate your watch before going into the field. www.time.govDetermine the number of seconds (down to the nearest ½ second) between your watch time and true time. This is the watch correction + or – from observed to true.
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