Deep-space laser-ranging missions ASTROD (Astrodynamical Space Test of Relativity using Optical Devices) and ASTROD I for astrodynamics and astrometry

TL;DR

The paper discusses the ASTROD and ASTROD I missions, which aim to use deep-space laser ranging for testing relativistic gravity and achieving high-precision solar-system mapping, impacting astrometry and reference frames.

Contribution

It introduces the missions' potential for high-precision solar astrodynamics and relativistic tests, emphasizing their role in advancing astrometry and gravitational physics.

Findings

High-precision planetary ephemeris possible

Second post-Newtonian gravity tests feasible

Implications for future astrometry and reference frames

Abstract

Deep-space laser ranging will be ideal for testing relativistic gravity, and mapping the solar-system to an unprecedented accuracy. ASTROD (Astrodynamical Space Test of Relativity using Optical Devices) and ASTROD I are such missions. ASTROD I is a mission with a single spacecraft; it is the first step of ASTROD with 3 spacecraft. In this talk, after a brief review of ASTROD and ASTROD I, we concentrate of the precision of solar astrodynamics that can be achieved together with implications on astrometry and reference frame transformations. The precision planetary ephemeris derived from these missions together with second post-Newtonian test of relativistic gravity will serve as a foundation for future precise astrometry observations. Relativistic frameworks are discussed from these considerations.