Active acoustic probing is important for supporting the investigation of icy subsurfaces and under-surface liquid water in potentially water-bearing habitable worlds. Many planetary orbital spacecraft and lander mission concepts have already been equipped with or are in the process of being equipped with state-of-the-art active sounding radar instruments. However, these subsurface radar instruments face challenges when it comes to icy subsurfaces and water-bearing worlds like Europa and Enceladus. The high attenuation of signals in briny ice and salty water hampers the ability to detect subsurface features below such layers, limiting the effectiveness of electromagnetic exploration in these environments. In contrast to electromagnetic based radar instruments, active elastic sounding technology is not limited by the presence of highly conductive layers, such as melt pockets or brine layers that are proposed as explanation of observed surface features on Europa. In this paper, we present our progress in developing the active Elastic Wave Analyzer for Icy Sub-surfaces (EWAIS), which may be feasible to probe kilometers-deep in ice with sensitivity sufficient to yield geological properties.
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