How GAIA can improve planetary ephemerides?

International audienceGAIA will have a big impact on the study of the dynamics of the main planets of our solar system. After a brief overview of the present accuracy and modeling of the planetary ephemerides, we introduce expected improvements brought by the GAIA mission: on the inner planet orbits with the GAIA asteroid astrometry and on outer planet orbits with the use of satellite astrometry and with new analysis of optical observations based on the GAIA star catalog