地球动力学扁率值对章动计算的影响

随着计算精度的提高，理论章动的计算中必须考虑地球动力学扁率数值选取的因素，探讨了地球动力学扁率值对刚体地球章动振幅和非刚体地球章动转换函数的影响，在刚体地球章动振幅的计算中，地球动力学扁率起着尺度因子的作用，更改善刚体地球章动的计算，需要更改黄经总岁差的数值。非刚体地球章动转换函数中所采用的简正模频率和常数都直接或间接地依赖地球动力学扁率值，它们对最后章动振幅的影响远远大于微角秒量级。在建立非刚体地球章动理论中，一个一致的自洽的地球动力学扁率值将能为地球章动序列的改善作出贡献。

Effect of Numerical Value of Earth Dynamical Flattening on Nutation Computation

The increasing accuracy of the modern observations requires to take into account the coefficients of nutation at the level of a few microarcseconds, so the choice of the numerical values of the Earth dynamical flattening has to be considered in the computation of a nutation series. In this paper, the effects of the value of the Earth dynamical flattening on rigid Earth nutation amplitudes and the transfer function of non-rigid Earth nutation are discussed. The value of the Earth dynamical flattening plays a scaling factor role in the computations of rigid Earth nutation amplitudes. In order to improve the computations of rigid Earth nutation, it has become necessary to revise the value of the general precession longitude. The normal mode eigenfrequencies and constants, adopted in the transfer function of non-rigid Farth nutation, directly or indirectly depend on the value of the Earth dynamical flattening. Its influence on the coefficients of nutation is far greater than microarcsecond .A consistent value of the Earth dynamical flattening will make a contribution to the improvement of the Earth nutation series in the construction of the nutation theory of a non-rigid Earth.