Mid-Infrared Compositional Spectral Parameters for the Lunar Thermal Mapper Instrument Onboard Lunar Trailblazer

The Lunar Trailblazer mission launched in February of 2025 with the goal of characterizing lunar surface water through a targeted campaign. One instrument on the mission, the Lunar Thermal Mapper (LTM), was tasked with measuring the surface temperature to compare with maps of the form and abundance of water on the lunar surface. LTM's secondary science goals were to identify regolith composition and thermophysical properties as exhibited by mid-infrared spectral features. Here we show the utility of LTM in distinguishing lunar regolith composition with its 11 narrow bands. Five spectral parameter products were developed to aid in early identification of regions of interest for follow-on spectral analyses. These products include the Christiansen feature (CF) value, weighted absorption center (WAC) value, WAC band depth, Transparency Roll-off, and a Diviner CF value equivalent. These products would be used mainly to flag these regions for more detailed follow-up study with the entire spectral capabilities of the mission instrumentation.