Mars and frame-dragging: study for a dedicated mission

TL;DR

This study explores the feasibility of a dedicated satellite mission around Mars to measure the gravitomagnetic Lense-Thirring effect, focusing on minimizing systematic errors from Mars's gravitational field.

Contribution

It proposes an optimal satellite configuration and data combination strategy to accurately measure relativistic effects around Mars, reducing bias from gravitational uncertainties.

Findings

Bias due to Mars's equatorial radius can be canceled with two probes at different inclinations.

Remaining gravitational uncertainties induce less than 1% bias in measurements.

Expected Lense-Thirring shifts are approximately 10 cm per year.

Abstract

In this paper we preliminarily explore the possibility of designing a dedicated satellite-based mission to measure the general relativistic gravitomagnetic Lense-Thirring effect in the gravitational field of Mars. The focus is on the systematic error induced by the multipolar expansion of the areopotential and on possible strategies to reduce it. It turns out that the major sources of bias are the Mars'equatorial radius R and the even zonal harmonics J_L, L = 2,4,6... of the areopotential. An optimal solution, in principle, consists of using two probes at high-altitudes (a\approx 9500-9600 km) and different inclinations, and suitably combining their nodes in order to entirely cancel out the bias due to \delta R. The remaining uncancelled mismodelled terms due to \delta J_L, L = 2,4,6,... would induce a bias \lesssim 1%, according to the present-day MGS95J gravity model, over a wide range of admissible values of the inclinations. The Lense-Thirring out-of-plane shifts of the two probes would amount to about 10 cm yr^-1.