Light propagation in the gravitational field of N arbitrarily moving bodies in 1PN approximation for high-precision astrometry

TL;DR

This paper develops a first post-Newtonian model for light propagation in the gravitational field of multiple arbitrarily moving bodies with complex structures, aiming to enhance high-precision astrometric measurements.

Contribution

It provides a comprehensive relativistic framework for modeling light trajectories considering arbitrary motions and multipole structures of bodies in the Solar system.

Findings

Derived explicit formulas for light trajectories in complex gravitational fields.

Achieved a model suitable for sub-micro-arcsecond astrometry.

Enhanced understanding of gravitational influences on light in dynamic systems.

Abstract

The light-trajectory in the gravitational field of N extended bodies in arbitrary motion is determined in the first post-Newtonian approximation. According to the theory of reference systems, the gravitational fields of these massive bodies are expressed in terms of their intrinsic multipoles, allowing for arbitrary shape and inner structure of these bodies. The results of this investigation aim towards a consistent general-relativistic theory of light propagation in the Solar system for high-precision astrometry at sub-micro-arcsecond level of accuracy.