Seismic characterization of the subsurface and anthropogenic noise at the LUNA Moon analog facility

The increased interest in crewed and robotic lunar exploration results in a need for high-quality testbeds for instruments, experiments-including seismological ones-and procedures, and for operations training. The LUNA analog facility is a new large-scale testbed on the DLR campus in Cologne, Germany, i.e. located in an urban environment that includes traffic, heavy machinery, and a neighboring international airport. We perform the first characterization of the site and its ambient wavefield, with a focus on anthropogenic signals, as relevant background information for future users of LUNA. Combining active and passive seismic measurements, we derive velocity models for the site down to the bedrock at 152 ± 13 m depth. We provide a preliminary characterization of the ambient noise on campus and discuss and interpret examples of common anthropogenic signals in detail, demonstrating their use e.g. for traffic monitoring with a single station, or as a repeating seismic source. This study showcases how relevant information for future seismological users of a planetary analog facility can be derived with comparatively limited means, the potential of single-station seismology for monitoring airborne and ground traffic, and hints at possible uses of the future permanent seismometer in LUNA.