Progress on the Astrometric Gravitation Probe design

TL;DR

The paper discusses the design and expected scientific improvements of the Astrometric Gravitation Probe, a space telescope aiming to test General Relativity with unprecedented precision using innovative optical techniques.

Contribution

It introduces a novel optical design for the space-based astrometric experiment, enhancing feasibility and robustness for precise gravitational measurements.

Findings

Expected two orders of magnitude improvement in testing gravity theories

Innovative Fizeau-like coronagraphic combination of telescopes

Dual field of view for observing different gravitational effects

Abstract

The Astrometric Gravitation Probe mission is a modern version of the 1919 Dyson-Eddington-Davidson experiment, based on a space-borne telescope with a permanent built-in eclipse, provided by a coronagraphic system. The expected improvement on experimental bounds to General Relativity and competing gravitation theories is by at least two orders of magnitude. The measurement principle is reviewed, in particular the principle of Fizeau-like combination of a set of individual inverted coronagraphs simultaneously feeding a common high resolution telescope. Also, the payload has a dual field of view property, in order to support simultaneous observations of stellar fields either very close, or far away, from the Sun, i.e. fields affected by either high or low light bending. We discuss a set of solutions introduced in the optical design to improve on technical feasibility and robustness of the optical performance against perturbations, in particular induced by manufacturing and alignment tolerances, and launch stresses.