A Review of Remote Sensing and In-Situ Methods for Lava Tube Identification and Characterization

Abstract

Lunar lava tubes have emerged as high-priority targets for future exploration and habitation due to their potential to shield astronauts from radiation, thermal extremes, and micrometeorite impacts. This paper reviews current and emerging methods for detecting subsurface cavities on the Moon, spanning gravimetric anomaly mapping, ground-penetrating and orbital radar sounding, passive seismic imaging, and magnetic field surveying. Recent gravimeter-based studies suggest that lava tubes buried more than 26 meters deep could be detected using instruments with resolutions around 25 μGal, based on terrestrial analog modeling. Complementary work has explored ambient seismic noise techniques, including fiber-optic distributed acoustic sensing, as an alternative to dense seismometer networks for subsurface imaging. Gravity field models derived from GRAIL data continue to offer untapped resolution for identifying subsurface voids, while morphological approaches using highresolution stereo imagery have improved characterization of pit entrances and collapse features. This review synthesizes the strengths, resolution limits, and mission-readiness of each technique, and situates them against magnetometer-based detection to assess complementary roles these methods could play in a multi-instrument approach to confirming and characterizing lunar lava tube networks