Science. 1960 Sep 23;132(3430):807-8. doi: 10.1126/science.132.3430.807.
Predictions of the orbit of the Transit 1B satellite were systematically in error until account was taken of a third-order gravitational harmonic. The amplitude deduced for this harmonic by O'Keefe from the Vanguard I orbit serves very well, even though the orbits and the methods of observation and orbit fitting for the two satellites are quite different.
直到考虑到三阶引力谐波,过境 1B 卫星轨道的预测才系统地出现错误。奥基夫从先锋 1 号轨道推导出的这个谐波的幅度非常好,即使两颗卫星的轨道以及观测和轨道拟合方法完全不同。