On possible a-priori "imprinting" of General Relativity itself on the performed Lense-Thirring tests with LAGEOS satellites

TL;DR

This paper investigates how the unmodeled effects of general relativity in Earth's gravity models may bias the measurement of the Lense-Thirring effect with LAGEOS satellites, suggesting the need to include relativity explicitly in data processing.

Contribution

It analytically demonstrates the potential imprint of general relativity on Earth's gravity models used for Lense-Thirring tests, highlighting a significant bias in current measurements.

Findings

General relativity can imprint on Earth's gravity models.

This imprint can bias Lense-Thirring measurements by a magnitude comparable to the effect itself.

Including relativity explicitly in models could reduce this bias.

Abstract

The impact of possible a-priori "imprinting" effects of general relativity itself on recent attempts to measure the Lense-Thirring precessions with the LAGEOS satellites orbiting the Earth and the terrestrial geopotential models by the dedicated mission GRACE is investigated. It is analytically shown that general relativity, not explicitly solved for in the GRACE-based models, may "imprint" their even zonal harmonic coefficients J_L at a non-negligible level, given the present-day accuracy in recovering them. This translates into a bias of the LAGEOS-based relativistic tests as large as the Lense-Thirring effect itself. Further analyses should include general relativity itself in the GRACE data processing by explicitly solving for it.