Numerical ephemerides of planets and the Moon - EPM and improvement of some astronomical constants

E. V. Pitjeva

Proceedings of the Journées 2003 "Systèmes de Référence Spatio-Temporels", A. Finkelstein & N. Capitaine (eds.), Institute of Applied Astronomy, St.Petersburg, 243-250 (2004)

Abstract

The current state of the last version of the planet part of EPM (Ephemerides of Planets and the Moon) ephemerides whose origin dates back to the 1970s, is presented. Ephemerides of the planets and the Moon have been numerically integrated in the PPN metric over a 125-year time interval (1886{2011). The dynamical model of EPM2003 ephemerides includes mutual perturbations from the nine planets, the Sun, the ve most massive asteroids, the Moon, lunar physical libration, perturbations from other 296 asteroids, as well as perturbations from the solar oblateness and the massive asteroid ring with constant mass distributions in ecliptic plane. EPM2003 ephemerides have resulted from a least squares adjustment to observational data totaling more than 280000 position observations (1913-2003) of different types. The set of astronomical constants have been obtained from accurate radiometric observations. The angles of the rotation between EPM2003 and the ICRF are (in mas): εx = 4.5 ± 0.8; εy = 0.8 ± 0.6; εz = 0.6 ± 0.4: The two versions of EPM2003 ephemerides have been constructed in TDB and TCB time scales as the independent variables of the equations.