The Laser Astrometric Test of Relativity: Science, Technology, and Mission Design

TL;DR

The LATOR experiment aims to test general relativity near the Sun with unprecedented precision using laser ranging and interferometry, potentially revealing new physics related to scalar fields.

Contribution

This paper presents the science goals, technological approach, and mission design for the novel LATOR experiment to test relativity with extreme accuracy.

Findings

Achieves 3 mm accuracy in interplanetary laser ranging.

Measures light deflection with 0.01 picoradian precision.

Improves gravitational deflection measurements by a factor of ~30,000.

Abstract

The Laser Astrometric Test of Relativity (LATOR) experiment is designed to explore general theory of relativity in the close proximity to the Sun -- the most intense gravitational environment in the solar system. Using independent time-series of highly accurate measurements of the Shapiro time-delay (interplanetary laser ranging accurate to 3 mm at 2 AU) and interferometric astrometry (accurate to 0.01 picoradian), LATOR will measure gravitational deflection of light by the solar gravity with accuracy of 1 part in a billion -- a factor ~30,000 better than currently available. LATOR will perform series of highly-accurate tests in its search for cosmological remnants of scalar field in the solar system. We present science, technology and mission design for the LATOR mission.