Mineralogical Characterization of the Lunar South Polar Region: 2. Exploring Mafic-Bearing Targets With Optimized Traverse Paths at Mons Kocher

1,2,3D. P. Moriarty III,1N. E. Petro,1B. A. Cohen
Journal of Geophysical Research: Planets Open Access Link to Article [https://doi.org/10.1029/2025JE009429]
1NASA GSFC, Greenbelt, MD, USA
2University of Maryland, College Park, MD, USA
3Center for Research andExploration in Space Science and Technology, Greenbelt, MD, USA
Published by arrangement with John Wiley & Sons

Several national space agencies and commercial entities are currently targeting the Moon’s south polar region for human and robotic exploration. Of particular interest are materials excavated and ejected from the Moon’s largest and oldest impact structure, the South Pole-Aitken Basin (SPA), as these ancient materials are a window into the early history of the Moon. SPA ejecta and impact melt are associated with the presence of Fe, Th, and pyroxene minerals. Mons Kocher, within the NASA Artemis exploration zone, exhibits elevated Fe, Th, and pyroxene abundance and presents a viable opportunity for Artemis astronauts to sample SPA material. Using orbital hyperspectral data from the Moon Mineralogy Mapper, we investigated the distribution of mafic minerals across the Mons Kocher region. We identified two types of mafic-bearing units: small (∼300 m) craters and sun-facing slopes. Spectral properties of the small craters (as well as the nearby ∼21 km Kocher crater) are consistent with low-Ca pyroxene, whereas the illuminated slopes exhibit similar pyroxenes with possible signatures of hematite-driven space weathering. Using least cost path models, we generate optimized traverse paths to the mafic craters through integration of topographic slope, average Earth visibility, and average solar illumination data.

Constraining the Hydration of Clay Minerals and Abundances of Amorphous Phases in Gale Crater, Mars

1,2Sean Czarnecki,1Craig Hardgrove,3Liz Rampe,2Patrick Gasda
Journal of Geophysical Research: Planets Open Access Link to Article [https://doi.org/10.1029/2025JE009199]
1Arizona State University, Tempe, AZ, USA
2Los Alamos National Laboratory, Los Alamos, NM, USA
3NASA JohnsonSpace Center, Houston, TX, USA
Published by arrangement with John Wiley & Sons

Both water and organic matter are required for the development and persistence of life.Phyllosilicates (clay minerals) have high surface areas that easily sorb water and organic matter. The Curiosityrover has investigated several hundred meters of stratigraphy in Gale crater, including where clays weredetected from orbit. Previous results have suggested that subsurface hydration is greatest in units with the mostabundant clays, suggesting that these minerals may be hydrated. Organics have also been found throughout Galecrater. Smectites are the most common and abundant phyllosilicates in Gale crater samples and can expand andsorb water and organics in interlayer sites. The most common organic sorption processes on Earth typicallyinvolve water or hydroxyl, so hydrated phyllosilicates are good candidates for organic preservation. Usingnewly derived subsurface hydration results with previously published mineralogy and geochemistry, we derivedmodeled constraints on the abundances of hydrated amorphous phases, “excess” water, and “excess” cations.These “excess” phases are not accounted for by published crystalline phase abundances or by amorphous phasesconstrained here. We found correlations between smectites and both “excess” water and “excess” cationabundances, indicating that smectites in Gale crater are hydrated and that cation bridging could be a mechanismfor sorption of organics. Our results also show the persistence of amorphous sulfates, opal‐A, and volcanic orimpact glass, which indicate low water‐rock interactions. Increased abundances of sulfates and glass instratigraphically higher samples may indicate lower water availability and environmental aridification duringthe time these units were being deposited.