REFINING THE RELATIVISTIC MODEL FOR GAIA: COSMOLOGICAL EFFECTS IN THE BCRS

Sergei Klioner, Michael Soffel
unpublished
This paper represents a first attempt of embedding the Barycentric Celestial Reference System, the fundamental relativistic reference system to be used for the modelling of Gaia observations, into some cosmological background. The general Robertson-Walker metric is transformed into local coordinates where the cosmologi-cal effects are represented as tidal potentials. A version of a cosmological BCRS is then suggested to lowest order. The effects of cosmological background on the motion of the
more » ... lar System are estimated and found to be completely negligible. The relation to the de Sitter and Schwarzschild-de Sitter solutions is discussed.
fatcat:wb3okbtq4nhx3byj3dcykum22q