caa a22 4500 467987505 CHVBK 20180323112536.0 cr unu---uuuuu 170328e19900601xx s 000 0 eng 10.1007/BF00049510 doi (NATIONALLICENCE)springer-10.1007/BF00049510 Capitaine N. Observatoire de Paris, URA11251CNRS, 61, Avenue de l'Observatoire, 75014, Paris, France aut The celestial pole coordinates [Elektronische Daten] [N. Capitaine] The coordinates of the Celestial Ephemeris Pole in the Celestial Reference System (CRS) can advantageously replace the classical precession and nutation parameters in the matrix transformation of vector components from the CRS to the Terrestrial Reference System (TRS). This paper shows that the new matrix transformation using these coordinates in place of the preceding parameters would be conceptually more simple, especially when associated with the use of the ‘non-rotating' origin on the instantaneous equator (Guinot 1979, Capitaine et al. 1986) and of a celestial reference frame as realized by positions of extragalactic sources. In such a representation, the artificial separation between precession and nutation is avoided and the practical computation of the matrix transformation only requires the knowledge of the two celestial direction cosines of the pole, instead of the large number of the quantities generally considered. The development of these coordinates is given as function of time so that their use is equivalent (when using the CRS defined by the mean pole and mean equinox of epoch J2000.0, the 1976 IAU System of Astronomical Constants and the 1980 IAU theory of nutation) to the one of the conventional series for the precession (Lieske et al. 1977) and nutation (Seidelmann 1982) parameters. Such a theoretical development should also be used in order to derive more directly the numerical coefficients of the celestial motion of the instantaneous equator from very precise observations such as VLBI. Kluwer Academic Publishers, 1990 Astrometry nationallicence precession nationallicence notation nationallicence rotation of the earth nationallicence Celestial Mechanics and Dynamical Astronomy Kluwer Academic Publishers 48/2(1990-06-01), 127-143 0923-2958 48:2<127 1990 48 10569 https://doi.org/10.1007/BF00049510 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00049510 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Capitaine N. Observatoire de Paris, URA11251CNRS, 61, Avenue de l'Observatoire, 75014, Paris, France aut NATIONALLICENCE 773 0- Celestial Mechanics and Dynamical Astronomy Kluwer Academic Publishers 48/2(1990-06-01), 127-143 0923-2958 48:2<127 1990 48 10569 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer