Assessing the feasibility of Distributed Acoustic Sensing (DAS) for moonquake detection

Moonquakes can provide valuable insights into the lunar interior and its geophysical processes. However, extreme scattering of the lunar seismic waves makes seismic phase identification and source characterization difficult. In recent years, Distributed Acoustic Sensing (DAS) technology has emerged as a promising tool for seismic monitoring on Earth by turning a fiber optic cable into a dense array of strainmeters. DAS array can detect the full wavefield even in highly scattering environments and track scattered phases that were previously aliased on the standard sparse seismic networks. This study assesses the feasibility of DAS for moonquake detection. We present synthetic DAS recordings demonstrating its suitability for capturing moonquake signals in environments with significant scattering and low seismic velocities. By comparing Apollo moonquake signals with DAS's current minimum noise floor observed in Antarctica's quiet conditions, we find that existing DAS technology can detect more than 60 % of moonquakes previously recorded by Apollo seismic sensors. With expected and achievable improvements in DAS equipment, detection rates could surpass 90 %. Our findings suggest that DAS could, on average, detect around 15 moonquakes daily, with large fluctuations depending on recording during lunar sunrise/sunset for thermal moonquakes and the moon's distance from perigee/apogee for deep moonquakes. The deployment of DAS on the Moon could mark a revolutionary step in lunar seismology, significantly enhancing our understanding of the Moon's internal structure.