Field Testing of Simulated Lunar Ice Characterization Using Ground Penetrating Radar Technology

Ground-penetrating radar (GPR) is a powerful geophysical method that can accurately characterize contrasting material boundaries within the subsurface in nearly any environment. Compared to other geophysical methodologies, GPR offers the greatest power output versus mass ratio, making it an excellent mechanism for rover technology. Surface mining exploration rovers can be augmented with GPR technology to scan the lunar subsurface for solid water ice bodies to be used in crucial future space endeavors. GPR allows mapping material interface boundaries such as ice, rocks, or metallic objects. The Moon is expected to contain solid water ice within its perpetually dark craters. Our preliminary research is focused on the first meter of depth within the lunar regolith since that is the initial target for potential ice excavation. It is here that solid water ice is expected to exist but in a currently unknown form. Preliminary testing was done to understanding the strengths and weaknesses of the applicable GPR equipment through experimental ice burial testing at a designated testing site. An experimental testbed containing engineered lunar simulant with approximated environmental lunar conditions is planned to be used to analyze the interactions between electromagnetic radio wave propagation and solid water ice. Testing will be done with multiple GPR devices with 50, 100, 500, and 1,000 MHz antenna frequencies. GPR devices equipped with 1,000 MHz antennas are expected to offer the greatest resolution for the depth of interest. Reflection coefficients and permittivity of materials are the key variables that are being addressed before successful characterization of lunar ice bodies. The collected radargram data will be organized into a dataset to be used as a reference for future mining rover missions equipped with GPR.