Gamma-ray and neutron spectrometers for lunar science and exploration

Orbital remote sensing data and sample studies have revealed much about the formation and evolution of the Moon. Future landed missions will investigate specific geologic features. For example, studies of unusual silicic volcanic features, rich in radioelements, such as the Gruithuisen Domes, will provide further insights into the Moon’s geochemical evolution. Measurements of elemental composition by nuclear spectroscopy will play an important role in these future missions, as it has throughout the history of lunar exploration. Here, we describe radiation sensor technology used for lunar applications, and their deployment in an environment that includes extreme temperature variations and damaging ionizing radiation. We highlight the development of a new rover-based instrument, part of the Lunar Vulkan Imaging and Spectroscopy Explorer (Lunar-VISE) mission to the Gruithuisen Domes. Aspects of the design of this CLYC-based spectrometer and its prospective performance, supported by analog geology studies, are presented.