Kinematical Relativistic Corrections for Earth's Rotation Parameters

摘要

Dynamical theories of the Earth's rotation like SMART97 (Bretagnon et al., 1998) are to be considered in a DGRS (dynamically non-rotating geocentric reference system) (Brumberg et al., 1996). Such a theory gives the explicit expressions in terms of TCG (Geocentric Coordinate Time) of three Euler angles relating a DGRS to the ITRS (International Terrestrial Reference System). These angular quantities together with their TCG derivatives enable one to get all of Earth's rotation parameters. At the same time, the analysis of observations results in the values for slightly different angles and their TCG derivatives characterizing the relationship between the ITRS and a KGRS (kinematically non-rotating geocentric reference system). The differences between these two sets of six quantities represent kinematical relativistic corrections due to geodesic precession, geodesic nutation, and luni-planetary terms. This paper presents these differences computed by means of the VSOP87 series (Bretagnon and Francou, 1988). In particular, in analyzing observations at the microarcsecond level, these expressions will permit an experimental check of geodesic precession in a manner that is more direct than that used today (Bertotti et al., 1987).