Local tests of gravitation with Gaia observations of Solar System Objects

TL;DR

This paper explores how Gaia's precise observations of Solar System Objects can be used to test and constrain various aspects of gravitational theories, including General Relativity and its modifications.

Contribution

It presents a preliminary sensitivity analysis of Gaia data for testing gravitational theories and measuring parameters like the Sun's quadrupole moment and PPN parameters.

Findings

Gaia observations can significantly constrain gravitational parameters.

Extended mission duration improves sensitivity to gravitational effects.

Preliminary results indicate potential for local tests of gravity theories.

Abstract

In this proceeding, we show how observations of Solar System Objects with Gaia can be used to test General Relativity and to constrain modified gravitational theories. The high number of Solar System objects observed and the variety of their orbital parameters associated with the impressive astrometric accuracy will allow us to perform local tests of General Relativity. In this communication, we present a preliminary sensitivity study of the Gaia observations on dynamical parameters such as the Sun quadrupolar moment and on various extensions to general relativity such as the parametrized post-Newtonian parameters, the fifth force formalism and a violation of Lorentz symmetry parametrized by the Standard-Model extension framework. We take into account the time sequences and the geometry of the observations that are particular to Gaia for its nominal mission (5 years) and for an extended mission (10 years).