¹Juulia-Gabrielle Moreau, ¹Argo Jõeleht, ^2,3Anna Losiak, ⁴Meng-Hua Zhu, ¹Jüri Plado
Icarus (in Press) Link to Article [https://doi.org/10.1016/j.icarus.2025.116856]
¹Department of Geology, University of Tartu, Ravila 14A, 50411 Tartu, Estonia
²Institute of Geological Sciences, Polish Academy of Sciences, Podwale 75, PL-50449 Wroclaw, Poland
³Lunar and Planetary Institute, Houston, USA
⁴State Kay Laboratory of Lunar and Planetary Sciences, Macau University of Science and Technology, Taipa, Macau, China
Copyright Elsevier

Sedimentary rocks often form the upper layers or the entire target rocks in impact events. Thermodynamic properties of sedimentary rocks related to porosity and water saturation affect the process of impact crater formation. The heterogeneous distribution of sedimentary facies can complicate the development and distribution of shock effects, especially in numerical modeling. This work focuses on the shock thermodynamic properties of carbonate rocks with differing porosity textures (e.g., isolated pores, interstitial porosity, elongated pores) and water saturation levels. Using mesoscale numerical modeling, we found that water saturation reduces shock temperatures compared to those in dry, porous carbonate rocks. The orientation of elongated pores and porosity lineations influences the shock temperature distribution and rock deformation at angles of 50–90° to the shock front. Additionally, due to complex shock wave interactions, interstitial porosity is key in creating temperature zonations around larger grains.

¹Rui Tahara et al. (>10)
Meteoritics & Planetary Science (in Press) Open Access Link to Article [https://doi.org/10.1111/maps.70066]
¹Japan Aerospace Exploration Agency, Sagamihara, Japan
Published by arrangement with John Wiley & Sons

NASA’s OSIRIS-REx mission successfully collected and returned ~121.6 g of bulk samples from the B-type, near-Earth asteroid (101955) Bennu to Earth in September 2023. Upon returning to Earth, the samples were transported to the NASA Johnson Space Center where most of the samples have been stored and processed. On August 22, 2024, 0.5 wt% of Bennu samples (0.663 g) and a contact pad that collected particles from the surface of Bennu were permanently transferred to JAXA from NASA based on a Memorandum of Understanding and a letter of agreement between the two agencies. Following this, all the Bennu samples have been curated under nitrogen-purged gloveboxes, called clean chambers in a clean room at the Extraterrestrial Sample Curation Center in Sagamihara. While maintaining the pristinity of samples at the curation, we conduct a series of nondestructive analyses, including near-infrared spectroscopy within the clean chambers. Bennu curation was conceptualized primarily based on the Hayabusa2 curation, whereas lessons learned from the Hayabusa2 curation were integrated into designing Bennu curation. Here, we describe preparations for the Bennu curation, with an emphasis on the differences from the Hayabusa2 curation.

^1,2,3Xuhang Zhang et al. (>10)
Earth and Planetary Science Letters 671, 119666 Open Access Link to Article [https://doi.org/10.1016/j.epsl.2025.119666]
¹Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
²Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
³Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
Copyright Elsevier

Understanding the elemental and isotopic composition of the Sun is key to reconstructing planetary formation, atmospheric evolution and solar activity over time. Noble gases from solar wind implanted into lunar regolith provide a unique archive of solar history, but their interpretation is complicated by implantation uncertainties and secondary processes (e.g., diffusion, regolith gardening, solar and galactic cosmic ray exposure). Here we report the isotopic composition of the noble gases (helium, neon, and argon) in thirty six high-purity plagioclase grains from Chang’e-5 lunar soil to assess the preservation of implanted solar wind in lunar materials. Compared with plagioclase from several Apollo sites, the grains retain a more pristine solar wind record, revealing a dynamic equilibrium between solar wind and cosmic ray irradiation and intense diffusive loss driven by localized heating likely due to micro-impacts or temperature gradients at the lunar surface. These coupled mechanisms explain the observed inter-grain He/Ne/Ar variations. Our data further indicate that kinetic diffusion during solar wind implantation, rather than post-implantation alteration, is the primarily driver of elemental fractionation relative to original solar wind values in plagioclase. Collectively, these findings reveal pathways of solar wind-driven noble gas retention and loss in lunar materials and further accounts for the presence of solar wind-derived He and Ne in the lunar exosphere. They also underscore the need to correct for process-related modifications when reconstructing past solar wind compositions, thereby enabling improved inference of solar evolution, planetary volatiles origins, and the initial solar nebula composition.

¹M. Yesiltas,¹T. D. Glotch
Meteoritics & Planetary Science (in Press) Link to Article [https://doi.org/10.1111/maps.70067]
¹Department of Geosciences, Stony Brook University, Stony Brook, New York, USA
Published by arrangemetn with John Wiley & Sons

CM chondrites have undergone varying degrees of aqueous alteration and thermal metamorphism on their parent bodies. Consequently, the petrologic grade of CM chondrites spans the entire type 2 scale (e.g., types 2.0–2.9). A 12236 is a very primitive petrologic type 2.9 carbonaceous chondrite that offers a unique window into the complex formation and evolution histories of CM chondrites. Based on its chemical composition, it is one of the least altered CM chondrites identified to date and one of the most primitive meteorites. Here, we present a comprehensive characterization of the organic and inorganic constituents of A 12236, determined through electron microscopy, micro-Raman, and s-SNOM nano-FT-IR spectroscopy. We identified FeNiS phases, including pentlandite, pyrrhotite, and troilite, within a fine-grained matrix composed predominantly of crystalline and amorphous silicates, including phyllosilicates. Raman spectroscopic results suggest that A 12236 experienced less thermal metamorphism than type 3 carbonaceous chondrites and contains polyaromatic organic matter with slightly differing structural order. Nano-FT-IR spectroscopy revealed chemically distinct aliphatic and aromatic organic phases, with observed compositional heterogeneity indicating variations in organic precursors and accreted materials. Correlation analysis highlights the complex associations between organic matter and phyllosilicates, along with evidence of differing aromatic compositions within the matrix. The varying abundances of nanoscale organics in different areas of A 12236 suggest that the organic matter is highly heterogeneously distributed within the matrix. Our findings demonstrate the effectiveness of nano-FT-IR spectroscopy for high-resolution, nondestructive analysis of extraterrestrial samples.

¹M. Simopoulou et al. (>10)
Journal of Raman Spectroscopy (in Press) Open Access Link to Article [https://doi.org/10.1002/jrs.6833]
¹Agricultural University of Athens, Laboratory of Mineralogy & Geology, Athens, Greece

We currently do not have a copyright agreement with this publisher and cannot display the abstract here

¹Ke Zhu (朱柯),²Nao Nakanishi,³Jan Render,³Quinn R. Shollenberger,⁴Tetsuya Yokoyama,⁴Akira Ishikawa,⁵Lu Chen
The Astrophysical Journal Letters 984, L54 Open Access Link to Article [DOI 10.3847/2041-8213/adc89c]
¹State Key Laboratory of Geological Processes and Mineral Resources, School of Earth Sciences, China University of Geosciences, Wuhan 430074, People’s Republic of China
²Department of Earth Sciences, Waseda University, Tokyo 169-8050, Japan
³Nuclear and Chemical Sciences Division, Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA 94550, USA
⁴Department of Earth and Planetary Sciences, Institute of Science Tokyo, Tokyo 152-8551, Japan
⁵Wuhan Sample Solution Analytical Technology Co., Ltd., Wuhan, People’s Republic of China

The recently proposed Yamato-type (CY) chondrites share significant similarities with CI chondrites and Ryugu. We present major and trace elemental, Re–Os, and mass-independent Ti, Cr, and Fe isotope data for seven CY chondrites. The elemental data along with isotopic compositions reveal two distinct lithologies, here designated as CY1 and CY2, potentially originating from two different parent bodies. Although sharing similarities with CM chondrites, CY2 chondrites have distinct Cr isotope compositions, arguing against a close genetic relationship. The CY1 lithology exhibits elemental abundances similar to CI chondrites/Ryugu as well as Fe, Ti, and Cr isotope compositions that closely overlap with those of CI chondrites/Ryugu. This suggests that CI chondrites, CY1 chondrites, and Ryugu accreted in the same region of the solar system and may even originate from the same parent body. In fact, we find that the reduced water content and certain volatile element abundances alongside increased sulfide content and mass-dependent O isotope enrichments observed in CY1 compared to CI chondrites could be attributed to an impact-induced heating event on the CI parent body. This impact likely disrupted the CI parent body, resulting in the ejection of both CI and CY1 lithologies. Furthermore, given that there are presently only five known CI meteorite specimens, the close chemical composition between CY1 and CI chondrites substantially expands the data set for comparisons and referrals to the bulk solar system composition for nonvolatile elements. Finally, we propose that the “CY1” chondrites could be called “CI1T,” while the designation “CY” chondrites could be restricted to “CY2” samples.

^1,2Runwu Li, ^1,2Ming Tang, ¹Jiaxi Wang
Earth and Planetary Science Letters 671, 119650 Link to Article [https://doi.org/10.1016/j.epsl.2025.119650]
¹Key Laboratory of Orogenic Belt and Crustal Evolution, MOE, School of Earth and Space Sciences, Peking University, Beijing 100871, China
²Research Institute of Extraterrestrial Material (RIEMPKU), School of Earth and Space Sciences, Peking University, Beijing 100871, China
Copyright Elsevier

The samples returned by the recent Chang’e-5 (CE-5) mission confirmed active lunar magmatism at least two billion years ago, which challenged the long-held view of an inactive Moon through much of its lifespan. However, the origin of this extended lunar magmatism remains mysterious. The CE-5 lunar soil and basalt fragments exhibit a strong fractionation between middle and heavy rare earth elements, a phenomenon rarely observed in the Apollo samples. We confirm this fractionation as a primary magmatic signature with measurements of the pyroxenes. By coupling phase equilibria modeling and element partitioning calculations, we show that this fractionation can only be produced if the magma source contained ∼5-10% garnet at a minimum depth of ∼700 km. We suggest the primary CE-5 magma may have originated from the lunar lower mantle. For melting to occur, one possibility is that convection may have been sustained in the deep lunar mantle until at least two billion years ago. Alternatively, the CE-5 magma may have tapped the melt-bearing layer near the core, as indicated by recent seismic observations.

¹Sarah Joiret, ^1,2Alessandro Morbidelli, ³Rafael de Sousa Ribeiro, ⁴Guillaume Avice, ⁵Paolo Sossi
Eartha and Planetary Science Letters 671, 119625 Link to Aricle [https://doi.org/10.1016/j.epsl.2025.119625]
¹Collège de France, Université PSL, 75005 Paris, France
²Laboratoire Lagrange, Université Cote d’Azur, CNRS, Observatoire de la Côte d’Azur, Boulevard de l’Observatoire, 06304 Nice Cedex 4, France
³Sao Paulo State University, UNESP, Campus of Guaratingueta, Av. Dr. Ariberto Pereira da Cunha, 333 – 6 Pedregulho, Guaratingueta – SP, 12516-410, Brazil
⁴Université Paris Cité, Institut de physique du globe de Paris, CNRS, 75005 Paris, France
⁵Institute of Geochemistry and Petrology, ETH Zürich, Sonneggstrasse 5, CH-8092 Zürich, Switzerland
Copyright Elsevier

Mars finished forming while the solar nebula was still present, and acquired its primordial atmosphere from this reservoir. The absence of a detectable cometary xenon signature in the present-day Martian atmosphere suggests that the capture of solar nebular gas was significant enough to dilute later cometary contributions. By quantifying the mass of cometary material efficiently retained on Mars, we place a lower bound on the mass of the primordial Martian atmosphere. To test the robustness of our conclusions, we use cometary bombardment data from two independent studies conducted within a solar system evolutionary model consistent with its current structure. Our calculations show that, even under the most conservative scenario, the minimal mass of the primordial martian atmospheres would yield a surface pressure of no less than 2.9 bar. Such a massive nebular envelope is consistent with recent models in which atmospheric capture is strongly enhanced by the presence of heavier species on Mars – due to outgassing or redox buffering with a magma ocean.

^1,2Haojin Hu,^1,3Xiaojia Zeng,⁴Yanxue Wu,¹Yuanyun Wen,^1,5Xiongyao Li,^1,5Jianzhong Liu
Journal of Geophysical Research (Planets)(in Press) Link to Article [https://doi.org/10.1029/2024JE008868]
¹Center for Lunar and Planetary Sciences, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, China
²University of Chinese Academy of Sciences, Beijing, China
³State Key Laboratory of Lunar and Planetary Sciences, Macau University of Science and Technology, Macau, China
⁴Analysis and Test Center, Guangdong University of Technology, Guangzhou, China
⁵CAS Center for Excellence in Comparative Planetology, Hefei, China
Published by arrangement with John Wiley & Sons

The continuous bombardment of lunar surfaces by asteroids and comets has modified the chemical, mineralogical, and physical properties of the lunar crust. Oxidizing agents from these impactors could alter the redox conditions on the Moon. However, no Fe3+-bearing phase crystallized from impact melt has been reported in the lunar regolith. In this study, a submicron-sized magnetite grain was observed in lunar impact glass from the Chang’e-5 regolith breccia. Our results demonstrate that this magnetite was directly crystallized from the lunar impact melt under oxidizing conditions (IW‒WM buffer). We propose that these impact events could play a role in altering the oxidizing conditions of the lunar crust. Furthermore, impact-melt-crystallized magnetite grains may contribute to some extent to lunar magnetic anomaly signatures, but they are likely a very minor component relative to Fe-Ni alloys.

¹Pan Yan,¹Zhi Cao,¹Zhiyong Xiao,²Yanxue Wu,¹Yunhua Wu,²Mingchao Xiong,²Zilei Chen,³Lifeng Zhong,⁴Dengfeng Li,⁴Qiaofen Liu
Journal of Geophysical Research (Planets)(in Press) Link to Article [https://doi.org/10.1029/2025JE008945]
¹Planetary Environmental and Astrobiological Research Laboratory, School of Atmospheric Sciences, Sun Yat-Sen University, Zhuhai, China
²Analysis and Test Center, Guangdong University of Technology, Guangzhou, China
³Southern Marin Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
⁴Guangdong Province Key Laboratory of Marine Resources and Coastal Engineering, School of Marine Sciences, Sun Yat-Sen University, Zhuhai, China
Published by arrangement with John Woiley & Sons

Microstructures are widespread on the surfaces of impact glasses in lunar regolith, recording intricate physical and chemical processes of regolith gardening. The Chang’e-6 mission returned the first regolith sample from the lunar farside, permitting investigation of regolith gardening on the farside and comparison with that on the nearside. Among over 400 glass particles handpicked from 1,500 mg of Chang’e-6 regolith, we investigated 178 impact glass beads, which were recognized based on their morphology, internal structure and geochemistry. The morphology and chemical compositions of microstructures on their surfaces are cataloged and compared with those reported on surfaces of lunar nearside samples, especially Chang’e-5 impact glasses. The various types of microstructures on surfaces of Chang’e-5 impact glasses are also observed on Chang’e-6 impact glasses, although the latter frequently exhibit a greater diversity of morphology and composition. The observations suggest that physical processes of regolith gardening are similar on the nearside and farside, which involve vapor, melt and/or solid phases, and with collision speeds much lower than those of extralunar impactors. On the other hand, there are other morphological types of microstructures on the surfaces of Chang’e-6 impact glass beads that were absent or rare on Chang’e-5 glasses, but they were reported on Apollo and Luna impact glasses. Their origin may be related to the older emplacement ages and/or more abundant exotic components in the protolith of Chang’e-6 regolith than that of Chang’e-5 regolith. During regolith gardening, chemical alterations of protoliths are nonuniform across the Moon, which are related to the contents of exotic components in the regolith.