EDP Sciences
Free access
Volume 383, Number 2, February IV 2002
Page(s) 729 - 737
Section Celestial mechanics and astrometry
DOI http://dx.doi.org/10.1051/0004-6361:20011791

A&A 383, 729-737 (2002)
DOI: 10.1051/0004-6361:20011791

Proper initial conditions for long-term integrations of the solar system

M. Arminjon

Laboratoire "Sols, Solides, Structures" CNRS / Université Joseph Fourier / Institut National Polytechnique de Grenoble, BP 53, 38041 Grenoble Cedex 9, France

(Received 20 April 2001 / Accepted 4 December 2001 )

An optimization program is used to re-adjust the initial conditions, in order to reproduce as closely as possible the predictions of a complete ephemeris by using simplified equations of motion in the numerical integration. The adjustment of the initial conditions is illustrated in the transition from the DE406 complete long-range ephemeris to a Newtonian model considering only the Sun and the four major planets. It is also used to best reproduce this same DE406 ephemeris, based on post-Newtonian equations for a system of mass points and including the Moon and asteroids, by using a Newtonian calculation corrected by the Schwarzschild effects of the Sun and restricted to the ten major bodies of the solar system.

Key words: celestial mechanics -- ephemerides

© ESO 2002