^1,2,3Yuchun Wu,²Nicolas Mangold,^1,3,4Yang Liu,⁵John Carter,¹Xing Wu,^4,6Lu Pan,⁷Qian Huang,^1,2,3Chaolin Zhang,^1,3Keyi Li,⁶Yongliao Zou
Journal of Geophysical Research (Planets)(in Press) Link to Article [https://doi.org/10.1029/2025JE008951]
¹State Key Laboratory of Solar Activity and Space Weather, National Space Science Center, Chinese Academy of Sciences, Beijing, China
²Laboratoire de Planétologie et Géosciences, Nantes Université, University Angers, Le Mans Université, CNRS, LPG UMR 6112, Nantes, France
³College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing, China
⁴National Key Laboratory of Deep Space Exploration, Hefei, China
⁵Institut d’Astrophysique Spatiale, Université Paris-Saclay, CNRS, Orsay, France
⁶School of Earth and Space Sciences, University of Science and Technology of China, Hefei, China
⁷Hubei Subsurface Multi-scale Imaging Key Laboratory, School of Geophysics and Geomatics, China University of Geosciences, Wuhan, China
Published by arrangement with John Wiley & Sons

Tyrrhena Terra, a region located in the cratered highlands between Hellas and Isidis Planitia on Mars, is distinguished by its extensive presence of hydrated minerals. Using 542 hyperspectral images from the Compact Reconnaissance Imaging Spectrometer for Mars, we detected 252 exposures of hydrated minerals. This region is characterized by a widespread distribution of Fe/Mg-smectites/vermiculites and chlorite, with additional detections of Al-phyllosilicates, zeolites, prehnite, hydrated silica, and carbonates. We classified the mineralogical detections in classes of impact crater diameters, locations in craters, and for those
20 km, their relative degradation stages. We found that craters
10 km display a lower mineral diversity than larger ones. In contrast, craters
20 km display a high mineral diversity, especially in central peaks, suggesting a strong influence of hydrothermal processes and deep excavation. Among this diameter range, fresh, young craters exhibit a much higher mineral diversity than degraded, old craters. Fe/Mg-phyllosilicates are dominant in the latter, as well as in sedimentary units of topographically low areas. These results indicate a long-term alteration cycle in the most ancient period, where the initial, diverse hydrated minerals—formed through exhumation and/or hydrothermal circulation within large impacts—were subsequently transformed by surface weathering and/or buried, dissolved, or eroded away by other post-impact processes, then transported and deposited in lowlands by fluvial erosion. Although Tyrrhena Terra is dominated by impact-related hydrated mineral detections, our study shows that the overprint of Noachian age weathering is visible within these detections.

¹Scott A. Eckley et al. (>10)
Journal of Geophysical Research (Planets)(in Press) Link to Article [https://doi.org/10.1029/2024JE008583]
¹Astromaterials Research and Exploration Science Division, Amentum – JETS2, NASA Johnson Space Center, Houston, TX, USA
Published by arrangement with John Wiley & Sons

Double drive tube 73001/2 was collected on the Light Mantle Deposit in the Taurus-Littrow Valley by Apollo 17 astronauts. It is a 4-cm diameter core that sampled up to 70 cm deep in a lunar landslide at the base of the North Massif. NASA kept these samples pristine and untouched in anticipation of advanced future analytical techniques, such as high-resolution X-ray computed tomography (XCT). Double drive tube 73001/2 was selected to be studied as part of the Apollo Next Generation Sample Analysis (ANGSA) program and was opened in November 2019 (73002) and February 2022 (73001). We discuss how XCT was utilized during the preliminary examination of these samples. This technique, which was unavailable the last time an Apollo drive tube was opened (1993), provides a three-dimensional (3-D) image of the interior of opaque objects. Prior to opening, high-resolution scans were collected of the full length of both cores, providing a novel 3-D archive of the intact lunar regolith. After opening, 352 > 4 mm particles were individually bagged and scanned, allowing for their lithological classification. We provide an example of the robustness of the individual particle data by analyzing ilmenite crystals (n = 350) in fourteen high-Ti basalt particles. Our results show that ilmenite generally has highly anisotropic shapes and can take on various external morphologies, indicating that 73001/2 likely sampled several lunar basalt flows. This paper illustrates the utility of XCT for curatorial and scientific purposes during ANGSA and demonstrates its value for future sample return missions.