On the impossibility of using certain existing spacecraft for the measurement of the Lense-Thirring effect in the terrestrial gravitational field

TL;DR

This paper critically examines the feasibility of using existing spacecraft with active compensation mechanisms, like GRACE, to measure the Earth's Lense-Thirring effect, concluding it is impractical due to gravitational and tidal perturbations.

Contribution

The paper provides a critical analysis demonstrating the impracticality of using certain existing spacecraft for Lense-Thirring measurements due to gravitational perturbations.

Findings

Uncancelled even zonal harmonic coefficients affect measurements

Time-dependent tidal perturbations mimic linear trends

Using existing spacecraft like GRACE is unfeasible for this purpose

Abstract

In the context of the currently ongoing efforts to improve the accuracy and reliability of the measurement of the Lense-Thirring effect in the gravitational field of the Earth it has recently been proposed to use the data from the existing spacecraft endowed with some active mechanisms of compensation of the non-gravitational accelerations like GRACE. In this paper we critically discuss this interesting possibility. Unfortunately, it turns out to be unpracticable because of the impact of the uncancelled even zonal harmonic coefficients of the multipolar expansion of the terrestrial gravitational potential and of some time-dependent tidal perturbations which would resemble as superimposed linear trends over the necessarily limited observational time span of the analysis.