北京地磁台天文方位角测量及误差分析

Azimuth measurement and error analysis at Beijing geomagnetic observatory

论述了北京地磁台天文方位标志的选点定位、造标埋设、方位角的测量方法。对８个观测墩位一个测点进行了方位角测量。通过计算方位角绝对精度ΔＡ＝２．４９″，平均观测均方差Ｍ＝±１．１４″，相当于三等天文观测精度，能满足地磁偏角６″的精度要求。

Two azimuth marks at Beijing Geomagnetic Observatory have been reset. We have measured the direction from 8 observing pillars to the azimuth mark. A new method of measuring the azimuth has been described. The accuracy of 2.49″±1.14″ is achieved by using this method. This accuracy which is in a certain degree of the third class astronomical observation can satisfy the requirement of 6″ accuracy for measuring the declination of the geomagnetic field.