^1,2Timo Hopp,^1,3Nicolas Dauphas,³Maud Boyet,⁴Seth A. Jacobson,⁵Thorsten Kleine
Science 390, 819-823 Link to Article [DOI: 10.1126/science.ado062]
¹Department of the Geophysical Sciences, The University of Chicago, Chicago, IL, USA
Max-Planck-Institut für Sonnensystemforschung, Göttingen, Germany
²Department of Earth and Planetary Sciences, The University of Hong Kong, Hong Kong, China
³Laboratoire Magmas et Volcans, Université Clermont Auvergne, Centre National de la Recherche Scientifique, Institut de Recherche pour le Développement, Observatoire de Physique du Globe de Clermont-Ferrand, Clermont-Ferrand, France
⁴Department of Earth and Environmental Sciences, Michigan State University, East Lansing, MI, USA
⁵Max-Planck-Institut für Sonnensystemforschung, Göttingen, Germany
Reprinted with permission from AAAS

The Moon formed from a giant impact of a planetary body, called Theia, with proto-Earth. It is unknown whether Theia formed in the inner or outer Solar System. We measured iron isotopes in lunar samples, terrestrial rocks, and meteorites representing the isotopic reservoirs from which Theia and proto-Earth might have formed. Earth and the Moon have indistinguishable mass-independent iron isotopic compositions; both define one end of the range measured in meteorites. Combining our results with those for other elements, we performed mass balance calculations for Theia and proto-Earth. We found that all of Theia and most of Earth’s other constituent materials originated from the inner Solar System. Our calculations suggest that Theia might have formed closer to the Sun than Earth did.

^1,2Ke Zhu,³Akira Yamaguchi,⁴Paolo A. Sossi,⁵Audrey Bouvier,⁶Lu Chen,⁷Peng Ni
Proceedings of the National Academy of Sciences of the USA 122, e2519759122 Link to Article [https://doi.org/10.1073/pnas.251975912]
¹State Key Laboratory of Geological Processes and Mineral Resources, Hubei Key Laboratory of Planetary Geology and Deep-Space Exploration, School of Earth Sciences, China University of Geosciences, Wuhan 430074, China
²Bristol Isotope Group, School of Earth Sciences, University of Bristol, Bristol BS8 1RJ, United Kingdom
³National Institute of Polar Research, Tokyo 190-8518, Japan
⁴Department of Earth and Planetary Sciences, ETH Zürich, Zürich 8092, Switzerland
⁵Bayerisches Geoinstitut, University of Bayreuth, Bayreuth 95547 95440, Germany
⁶Wuhan Sample Solution Analytical Technology Co., Ltd.,Wuhan 430075, China
⁷Department of Earth, Planetary, and Space Sciences, The University of California Los Angeles, Los Angeles, CA 90095

The angrite parent body (APB) is the most volatile-depleted among known differentiated bodies in the Solar System, yet the mechanisms responsible remain poorly constrained. Here, we present high-precision nickel (Ni) isotope data from a suite of angrite samples to reconstruct the APB’s volatile depletion history. Plutonic angrites contain unusually high proportions of metallic iron and exhibit chondritic δ60/58Ni values (0.202 ± 0.028‰; per mille mass-dependent 60Ni/58Ni deviation relative to National Institute of Standards and Technology (NIST) Standard Reference Material (SRM) 986). These observations are consistent with a homogeneous Ni isotope composition of the APB after core formation and the subsequent incorporation of endogenous core material in plutonic angrites. In contrast, a dunite and megacrystic olivines from volcanic angrites, derived from the mantle, display suprachondritic δ60/58Ni values (0.4 to 0.7‰). We argue that these values are consistent with Ni loss via evaporation during a high-energy impact that follows an initial stage of volatile loss from a magma ocean generated by 26Al heating. Thermodynamic modeling confirms Ni to be more volatile than Mn, Fe, Si, and Mg during evaporation from silicate liquids, in agreement with the observed relative magnitude of isotopic fractionation. Volcanic angrite matrices show variable and often subchondritic δ60/58Ni values (down to −0.5‰), reflecting mixing with isotopically heavy megacrystic olivines and recondensation of light Ni vapor onto the crust. These findings imply that volatile elements are stratified (core–mantle–crust) in the APB and provide direct isotopic evidence for impact-driven vapor loss and recondensation on a differentiated planetary body.

¹Makoto Kimura, ^2,3Michael K. Weisberg, ⁴Richard C. Greenwood, ^1,5Akira Yamaguchi
Geochemistry (Chemie der Erde) 85, 126343 Link to Article [https://doi.org/10.1016/j.chemer.2025.126343]
¹National Institute of Polar Research, 10-3 Midoricho, Tachikawa, Tokyo, 190-8513, Japan
²Kingsborough College and Graduate Center of the City University of New York, USA
³American Museum of Natural History, New York, USA
⁴Planetary and Space Sciences, The Open University, Milton Keynes, MK7 6AA, United Kingdom
⁵Department of Polar Science, the Graduate University for Advanced Studies, SOKENDAI, 10-3 Midoricho, Tachikawa, Tokyo, 190-8518, Japan
Copyright Elsevier

In this paper, we examine the diverse features of CM (Mighei-type) and related carbonaceous chondrites, including their petrologic classification, secondary heating, brecciation, and we explore anomalous CM-like chondrites. CM chondrites experienced varying degrees of aqueous alteration, resulting in a range of petrologic subtypes from 3.0 to 2.0. The most abundant subtypes are 2.3–2.0, which may reflect melting of significant amounts of ice, resulting in the formation of the heavily altered CM chondrites in the inner regions of the parent body. Additionally, some CM and related chondrites have undergone secondary heating after aqueous alteration. The source of heat for these chondrites is still uncertain, but impacts are the most likely the cause due to the evidence for a short duration of heating. CM chondrites are mainly genomict breccias and contain clasts of various petrologic grade and degree of heating, though some CMs contain xenolithic clasts. Highly recrystallized clasts are particularly important, as they might have formed in the interior, hotter regions of the CM parent body. Subsequently, these clasts may have been mixed with other typical CM lithologies due to impact events. CM chondrite fragments are commonly found in other meteorites, such as HED meteorites and ordinary chondrites. This indicates a widespread distribution of CM chondrite fragments in the main asteroid belt, with incorporation into other meteorites taking place significantly later than chondrule formation. There have been numerous descriptions of anomalous CM or related chondrites. We tentatively classify these anomalous CMs into four categories: highly 16O-rich, medium 16O-rich, an unusual mineral group, and others. However, the processes involved in the formation of these anomalous chondrites and their relationships to the more typical CMs remain unclear, as detailed documentation of most of the anomalous CMs is currently lacking. CM chondrites primarily consist of chondrules, refractory inclusions, opaque minerals, and a matrix material, similar to other C chondrites. The petrographic and bulk chemical features of CMs are most similar to CO chondrites. However, CM and CO chondrites did not originate from a single parent body. CM chondrites provide valuable information about the conditions and processes that operated in the outer region of the early solar system.

¹Justin R. Filiberto et al. (>10)
Geochemistry (Chemie der Erde)(in Press) Open Access Link to Article [https://doi.org/10.1016/j.chemer.2025.126316]
¹Astromaterials Research and Exploration Science (ARES) Division (XI), NASA Johnson Space Center, Houston, TX 77059, USA
Copyright Elsevier

One of the biggest unknowns about Venus is how volcanically active it is today. Venus has a similar size and density to Earth, suggesting it may have a comparable composition, and therefore it is expected to be volcanically active; however, exploring Venus and confirming current volcanic activity is difficult because of the thick omnipresent optically opaque clouds that hamper traditional observations of the lower atmosphere and surface. Further, surface conditions make long-lived missions challenging. Despite the difficulty, there have been tantalizing hints of currently active or very recent volcanism. Here, we review what is known about active volcanism, point out gaps in knowledge to be addressed, and highlight techniques and approaches that need to be developed before the new decade of Venus exploration. It is crucial to constrain the activity and rate of volcanism today and through time to begin to understand the geodynamic state of the planet.
We find that the combination of all evidence strongly indicates that Venus is volcanically active today. The best evidence for active volcanism comes from combining data sets and approaches – specifically at Idunn Mons, Maat Mons, and Aramaiti Corona – in contrast to those from a single study or data set alone. Considering the evidence for activity, observations do not favor so-called “catastrophic” models of resurfacing, instead they are better represented by ongoing regional scale events. To reliably detect and characterize active or recent effusive basaltic volcanism new missions must collect high-resolution imaging, repeat observations, radar polarimetry, evidence of outgassing, and high-resolution topographical data that provide insights into surface changes over time. The ability to capture and interpret these data is vital for understanding Venus’s geological activity, particularly in regions where volcanic processes are suspected to be ongoing.

¹Peter Mc Ardle,¹Rhian H. Jones,^2,3,4Luke Daly,¹Romain Tartèse,⁵Patricia L. Clay,⁵Brian O’Driscoll,¹Ray Burgess,⁶William Smith,⁶Colin How,¹Lewis Hughes
Meteoritics & Planetary Science (in Press) Open Access Link to Article [https://doi.org/10.1111/maps.70073]
¹Department of Earth and Environmental Sciences, University of Manchester, Manchester, UK
²School of Geographical and Earth Sciences, University of Glasgow, Glasgow, UK
³Department of Materials, University of Oxford, Oxford, UK
⁴Australian Centre for Microscopy & Microanalysis, University of Sydney, Camperdown, New South Wales, Australia
⁵Department of Earth and Environmental Sciences, University of Ottawa, Ottawa, Ontario, Canada
⁶School of Physics and Astronomy, University of Glasgow, Glasgow, UK
Published by arrangement with John Wiley & Sons

Enstatite chondrites formed under extremely reducing conditions in the protoplanetary disk. They are derived from two or more parent bodies, EH and EL, and both EH and EL groups contain petrologic type 3–6 samples. The rare lithophile- and halogen-bearing sulfide, djerfisherite, occurs in low abundance in enstatite chondrites, most frequently in the EH3 chondrites. In some EH3 chondrites, but not in EL chondrites, djerfisherite is associated with a fine-grained mineral assemblage, termed the “Qingzhen Reaction,” which has previously been interpreted as an alteration product of djerfisherite. The Qingzhen Reaction is notable as perhaps the only record of fluid-mediated alteration on the EH parent body. In this study, we undertook a high-resolution chemical and mineralogical analysis of the Qingzhen Reaction and its djerfisherite host, in order to determine its composition, relationship to djerfisherite and its formation environment. We show that the Qingzhen Reaction is an alteration product of djerfisherite, predominantly comprised of porous troilite with remnant djerfisherite. Trace quantities of halite and (likely) sphalerite are also present. We suggest that the Qingzhen Reaction formed by the interaction of an anhydrous fluid with djerfisherite on the EH parent body.

¹G. Lopez-Reyes et al. (>10)
Journal of Geophysical Research (Planets)(in Press) Open Access Link to Article [https://doi.org/10.1029/2025JE008943]
¹ERICA Research Group and LaDIS. Universidad de Valladolid (Spain), Valladolid, Spain
Published by arrangement with John Wiley & Sons

The Mars 2020 Perseverance rover introduced Raman spectroscopy to in situ planetary exploration for the first time when it landed in Jezero crater on Mars in February 2021. The SuperCam instrument onboard Perseverance is a multi-analytical tool capable of acquiring time-resolved Raman data from Martian targets at standoff distances of a few meters. This is a particularly challenging task due to the operational constraints, the harsh conditions on the Martian surface, and especially the very fine-grained nature of the Martian soil. To address these challenges, the SuperCam Raman team has invested significant effort into optimizing both the acquisition and post-processing of Raman data collected on Mars, as detailed in this work. Additionally, this paper reviews and discusses the detections made by SuperCam Raman during the first 1,000 sols (almost 3 Earth years) of the Mars 2020 mission. During this period, SuperCam Raman data provided key insights into the mineralogy of Jezero throughout the Crater, Delta, and Margin Campaigns. Key detections include olivine, carbonates, perchlorates, and sulfates (such as anhydrite), identified in both abraded patches and natural surfaces. The high specificity of Raman spectroscopy enables the unequivocal identification of these minerals, allowing for rapid and direct interpretation of Jezero’s mineralogy, especially when combined with other techniques from SuperCam or others on the rover. Furthermore, this paper compiles the spectra acquired from the SuperCam Calibration Target samples on Mars, including studies on the degradation of the Ertalyte (PET), an organic polymer sample and analyses of diamond, apatite, and other reference materials.

¹Weronika Ofierska, ¹Max W. Schmidt, ¹Christian Liebske, ¹Paolo A. Sossi
Earth and Planetary Science Letters 673, 119691 (in Press) Open Access Link to Article [https://doi.org/10.1016/j.epsl.2025.119691]
¹Department of Earth and Planetary Science, ETH, Zürich, Switzerland
Copyright Elsevier

Owing to the incompatibility of K, rare-earth elements (REE) and P in silicate minerals relative to melt, the KREEP component, found on the near-side of the Moon, is thought to have formed through protracted crystallisation of the Lunar Magma Ocean (LMO). Our fractional crystallisation experiments simulate the final stages of LMO crystallisation, from plagioclase onset to the last eutectic melt remnants. Results show the LMO liquid to remain saturated in olivine ± orthopyroxene ± Cr-spinel up to 74 % solidification (PCS), transitioning to plagioclase+clinopyroxene (cpx) from 1200 °C (74 PCS) to 1120 °C (88 PCS). The plagioclase+cpx+quartz cotectic is reached at 1080 °C (92.3 PCS), with liquid immiscibility and a crystal assemblage of plagioclase+augite+Ti-spinel+ilmenite+quartz occurring at 1030 °C (98.8 PCS), until nearly complete crystallization is reached at 1000 °C (99.5 PCS). Mineral/melt (plagioclase, pigeonite, high-Ca cpx) and melt/melt partition coefficients for K, REE, P, Zr, Hf, Nb, Th, and U were determined. They are used to model melt evolution to 99.5 PCS, showing that fractional crystallisation alone replicates KREEP’s REE profile and the above trace elements, yet, distinct Lu/Hf (and U/Pb) ratios suggest additional processes. Assuming a finite oxygen budget in the LMO and incompatible behaviour of Fe3+, the Eu anomaly of KREEP is best reproduced by a model in which oxygen fugacity (
) evolves from one log unit below to 1.5 log units above the iron-wustite buffer (IW-1 to IW+1.5) from 0 PCS to 99.4 PCS. Minor dacitic melt separation (1–5 % of the melt remaining at 1030 °C) sequestering K from REE+P is consistent with but unnecessary for KREEP formation; nevertheless, a second-stage partial re-melting of these dacites could match observed FeO and incompatible element abundances of lunar granites.

¹Francisca S. Paiva,^2,3Silvio Sinibaldi
Journal of Geophysical Research (Planets)(in Press) Open Access Link to Article [https://doi.org/10.1029/2025JE009132]
¹KU Leuven, Leuven, Belgium
²European Space Agency, Noordwijk, The Netherlands
³The Open University, Milton Keynes, UK
Published by arrangement with John Wiley & Sons

Recent detections of water ice in the permanently shadowed regions (PSRs) at the lunar poles have reignited scientific and commercial interest in the exploration of Earth’s closest neighbor. The frigid temperatures in PSRs operate as cold traps for volatiles and may represent large reservoirs of materials, including water ice and prebiotic organic molecules, delivered to the Earth-Moon system through meteorite or cometary impacts over billions of years (Crawford, 2006, https://doi.org/10.1017/s1473550406002990). Nonetheless, scientific investigations of lunar poles rely on the absence of extraneous volatiles introduced during lunar missions, which may hide pristine evidence of such materials. In the present work, we develop a numerical model for the transport of spacecraft exhaust volatiles on the Moon. Using ESA’s Argonaut missions as a case study, featuring a descent at the lunar South Pole, we apply this model to assess the potential impact of organic contamination from lunar landers on scientific research of lunar ice chemistry by tracing the migration of methane
molecules to the PSRs. Our simulation results suggest that approximately half of the released
molecules end up trapped in PSRs at the South or North poles within 7 lunar days, with their distribution dictated by interactions with the lunar surface. Moreover, cross-contamination between poles proves significant, as approximately
of molecules become trapped in the north polar region, despite only a limited fraction of these falling within the latitude limit of
defined for Category IIb in COSPAR Planetary Protection Policy.

¹Angelina Minocha,¹Ryan C. Ogliore,^2,3Paul K. Carpenter,^2,3Christopher Yen,^2,3Bradley L. Jolliff
Journal of Geophysical Research (in Press)(in Press) Open Access Link to Article [https://doi.org/10.1029/2024JE008614]
¹Physics Department, University of Central Florida, St. Louis, MO, USA
²McDonnell Center for the Space Sciences, Washington University in St. Louis, St. Louis, MO, USA
³Department of Earth, Environmental, and Planetary Sciences, Washington University in St. Louis, St. Louis, MO, USA
Published by arrangement with John Wiley & Sons

We have developed the Quantitative Microanalysis Explorer, or QME-Tool, a web-based platform for visualization of large imaging data sets and interrogation of quantitative elemental maps acquired by electron microprobes. Using a combination of open-source JavaScript libraries and custom scripts, the QME-Tool can be used to quickly identify interesting mineral and lithologic phases in a sample by comparing backscattered-electron (BSE), optical, and X-ray images, extract quantitative chemical composition in regions from electron-probe microanalysis (EPMA) stage maps, and easily share data and sample locations with colleagues. We have used the QME-Tool to study regolith contained in 12 petrographic thin sections of the Apollo 17 double-drive tube 73001/2 as part of the Apollo Next Generation Sample Analysis (ANGSA) Program. As an example of the utility of the QME-Tool, we have characterized a ∼500 × 750 μm basaltic lithic clast located in the 73002,6016 polished thin section, using a BSE image, quantitative EPMA stage maps, optical reflected light, and transmitted light in both plane-polarized and crossed-polarized images. In addition to non-destructive quantitative composition extraction, we examine phase chemistry and compute a bulk composition for the clast as well as a supervised classification (using pre-defined mineral clusters) according to its mineralogy. The data show that in its major element composition, the clast is essentially similar to ilmenite basalt 70017. This connection is used to argue that the high-Ti basalt clasts in the drive tube originated from impacts into the valley floor and help reconstruct the emplacement mechanism of the light mantle deposit.

^1,2Miguel Arribas Tiemblo,¹Pedro Rayo,¹María-Paz Martín-Redondo,¹Felipe Gómez
Journal of Geophysical Research (Planets)(in Press) Open Access Link to Article [https://doi.org/10.1029/2025JE009070]
¹Centro de Astrobiología (CAB), CSIC-INTA, Madrid, Spain
²Universidad de Alcalá de Henares (UAH), Madrid, Spain
Published by arrangement with John Wiley & Sons

Amino acids are an extremely heterogeneous group of biomolecules essential for life on Earth. Their biosignatures are expected to be easily degraded on the Martian surface as the absence of a thick atmosphere and a magnetosphere leads to most of the solar radiation directly reaching its surface. To determine the preservation of amino acids in the Martian regolith, and their detectability, we exposed protein-sourced and free amino acids to UV-B radiation. This was done while in contact with different particle size ranges of two Martian regolith simulants. Bulk analysis through High Performance Liquid Chromatography (HPLC) showed that UV-B radiation led to little damage across all samples, mainly targeting sensitive amino acids like tyrosine, histidine, tryptophan and methionine. The two Martian simulants were divided into five particle size ranges. Smaller particles (<0.045 mm) led to higher recoveries than bigger ones (>0.500 mm), likely through their high specific surface area. Raman spectroscopy offered localized surface information, which HPLC was unable to. One of the simulants (MMS-2) is rich in iron oxides like hematite, which likely prevented any detection by absorbing the excitation wavelength of the laser. Irradiation also led to widespread loss of signal of all amino acids. Overall, the limitations of both techniques were compensated by each another, which allowed for the precise characterization of the chemical alterations suffered by amino acids in these conditions.