平黄经
- 网络Mean longitude
平黄经-
本文从分析等高仪同一夜晚两相邻星组的组间差入手，证实了不论在纬度方面还是在经度方面，组间差的变化率都是存在的，且与平太阳黄经有关。
From the analysis of the difference between two neighbouring groups obtained with an astrolabe in the same night , the existance ( with regard to both latitude and longitude ) of the rate of change of the difference between two neighbouring star groups is discovered .