天文学进展2000，Vol.18Issue(4)：283-292,10.
地球动力学扁率及其与岁差章动的关系
The Earth Dynamical Flattening and Its Relation to Precession and Nutation
摘要
Abstract
The luni-solar precession, derived from the general precession in longitude, is one of the important parameters in astronomy. It relates to the Earth dynamical flattening which value can be obtained from the astronomical observation or from different Earth models. The Earth dynamical flattening plays an important role in the computations of nutation theory. Its values, determined from different kinds of observations and models are reviewed. Moreover, its relation to precession and its effect on nutation computation are discussed. The theoretical nutations of a non-rigid Earth are computed from a convolution of the rigid Earth nutation amplitude with a transfer function accounting for the geophysical parameters influencing the Earth rotation. The value of the Earth dynamical flattening correspounds to a scale in the rigid Earth nutation series.In order to improve the amplitudes of the rigid Earth nutation series, it become necessary to revise the IAU 1976 value of the general precession in longitude. The normal mode eigenfrequencies and constants adopted in the transfer function, depend directly or indirectly on the Earth dynamical flattening. The values of the Earth dynamical flattening, used in computing the amplitudes of the rigid Earth nutation series as well as the normal mode eigenfrequencies and constants of the transfer function, are not consistent in IAU 1980 nutation theory. The increasing accuracy of modern observations requires to take into account its influence on the nutation amplitudes at the level of a few microarcseconds. The interpretation and selection for different values of the Earth dynamical flattening will have to be approached in the construction of the future nutation theory of a non-rigid Earth.关键词
黄经总岁差－地球动力学扁率一非刚体地球章动振幅Key words
general precession in longitude－Earth dynamical flattening－non-rigid Earth nutation amplitude分类
天文与地球科学引用本文复制引用
夏一飞..地球动力学扁率及其与岁差章动的关系[J].天文学进展,2000,18(4):283-292,10.基金项目
国家自然科学基金重点资助项目(19833010) （19833010）
