Report of the Science Community Workshop on the proposed First Sample Depot for the Mars Sample Return Campaign

MSR Campaign Science Group (MCSG) et al. (>10)
Meteoritics & Planetary Science (in Press) Open Access link to Article [doi: 10.1111/maps.139811]
Published by arrangement with John Wiley & Sons

The Mars 2020/Mars Sample Return (MSR) Sample Depot Science CommunityWorkshop was held on September 28 and 30, 2022, to assess the Scientifically-ReturnWorthy (SRW) value of the full collection of samples acquired by the rover Perseverance atJezero Crater, and of a proposed subset of samples to be left as a First Depot at a location within Jezero Crater called Three Forks. The primary outcome of the workshop was thatthe community is in consensus on the following statement: The proposed set of ten sampletubes that includes seven rock samples, one regolith sample, one atmospheric sample, andone witness tube constitutes a SRW collection that: (1) represents the diversity of theexplored region around the landing site, (2) covers partially or fully, in a balanced way, allof the International MSR Objectives and Samples Team scientific objectives that areapplicable to Jezero Crater, and (3) the analyses of samples in this First Depot on Earthwould be of fundamental importance, providing a substantial improvement in ourunderstanding of Mars. At the conclusion of the meeting, there was overall communitysupport for forming the First Depot as described at the workshop and placing it at theThree Forks site. The community also recognized that the diversity of the Rover Cache (thesample collection that remains on the rover after placing the First Depot) will significantlyimprove with the samples that are planned to be obtained in the future by the Perseverancerover and that the Rover Cache is the primary target for MSR to return to Earth.

Extraterrestrial dust flux monitoring at Antarctic Vostok station: New collection of extraterrestrial spherules fallen from May to September 2017

1Y. O. CHETVERIKOV,1,2V. F. EZHOV,3,4M. S. GLUKHOV,5,6E. M. IVANKOVA,2A. S. LOSHACHENKO,2V. D. KALGANOV,2,7O. V. YAKUBOVICH
Meteoritics & Planetary Science (in Press) Link to Article [doi: 10.1111/maps.13991]
1Petersburg Nuclear Physics Institute named by B. P. Konstantinov of National Research Center “Kurchatov Institute”,Gatchina, Russia
2Saint Petersburg State University, St. Petersburg, Russia
3Kazan Federal University, Kazan, Russia
4Zavaritsky Institute of Geology and Geochemistry, Ural Branch of the Russian Academy of Sciences, Yekaterinburg, Russia
5Institute of Macromolecular Compounds, Russian Academy of Sciences, St. Petersburg, Russia
6Kirov Military Medical Academy, St. Petersburg, Russia7Institute of Precambrian Geology and Geochronology, Russian Academy of Sciences, St. Petersburg, Russia
Published by arrangement with John Wiley & Sons

Dust particles obtained by filtering fresh snow collected from May to September2017 in the vicinity of Vostok station in Antarctica were examined using a scanning electronmicroscope. The collection of dust particles contains 197 spherules ranging from 0.5 to 117μmin diameter, the most abundant ones (n=188) by far being iron oxide spherules. Analyses ofmeteorological and human activity data suggest an extraterrestrial origin of most of thespherical particles. The particle size distribution histogram showed a smooth increase in theirnumber with decreasing size and a dramatic drop at sizes smaller than 3μm. The number ofspherical particles has an uneven distribution over time, with an intense peak in July 27–28,2017 which correlates by dates with the peak of the Southern Delta Aquariids meteor shower.The size distribution of the particles collected during the same period indicates the presenceof a mechanism that accelerates their fall to the Earth. We propose that they are effectivecenters of condensation of ice crystals in stratospheric clouds. Our data indicate thatcollection of micrometeorites with sizes of several microns from the fresh snow is possible,opening a new way for sampling micrometeorites, including separate meteor showers.

Mineralogy of explosive and effusive volcanic edifices in the Marius Hills Volcanic Complex

1,2,3,4Marie J.B. Henderson,4Briony H.N. Horgan,5Samuel J. Lawrence,6Julie D. Stopar,6Lisa R. Gaddis
Icarus (in Press) Link to Article [https://doi.org/10.1016/j.icarus.2023.115628]
1Solar System Exploration Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
2Center for Space Sciences and Technology, University of Maryland, Baltimore County, Baltimore, MD 21250, USA
3Center for Research and Exploration in Space Science and Technology, NASA/GSFC, Greenbelt, MD 20771, USA
4Purdue University, West Lafayette, IN 47907, USA
5NASA Johnson Space Center, Houston, TX 77058, USA
6Lunar and Planetary Institute, Houston, TX 77058, USA
Copyright Elsevier

The Marius Hills Volcanic Complex exhibits the highest concentration of extrusive volcanic landforms on the Moon, in the form of both domes and cones. The interpretive advancements made in this investigation result from improved spectral resolution and analysis techniques. Moon Mineralogy Mapper (M3) spectral analysis shows that the rounded landforms in MHVC exhibit spectra consistent with glass, confirming a cinder cone with an explosive volcanic origin. The presence of scoria-like glass-rich pyroclasts that should be distinct from the glass beads collected during Apollo. This research provides evidence that spectroscopy can identify volcanic landforms when visible images of the morphology are inconclusive, which is essential for future exploration of volcanic terrains. The likely concurrent eruption of the domes and cones with the differences in the mineralogy of the resulting edifices (e.g., presence of glass) add supporting evidence to the hypothesis that extrinsic properties (e.g., ascent rate), not changes in magma composition (e.g., amount of volatiles), led to the different volcanic morphologies. Combining the morphology and the spectral data, we hypothesize that the magma evolution of the region was long-lived and with distinct early edifice-forming and later mare-forming episodes. The long-lived volcanism recorded in multiple volcanic units within close proximity in MHVC would be ideal for future exploration and eventual sample return.

The high-temperature origin of hydrogen in enstatite chondrite chondrules and implications for the origin of terrestrial water

1Dorian Thomassin,1Laurette Piani,1Johan Villeneuve,2Marie-Camille Caumon,1Nordine Bouden,1Yves Marrocchi
Earth and Planetary Science Letters 616, 118225 Link to Article [https://doi.org/10.1016/j.epsl.2023.118225]
1Université de Lorraine, CNRS, CRPG, UMR 7358, Nancy, France
2Université de Lorraine, GeoRessources, UMR 7359, Nancy, France
Copyright Elsevier

Due to their numerous isotopic similarities to terrestrial rocks, enstatite chondrites (ECs) are commonly proposed as Earth’s main building blocks. Although ECs contain sufficient H concentrations to account for the mass of Earth’s oceans, the physicochemical process(es) behind their H incorporation remain under constrained. Here, we combined secondary ion mass spectrometry analyses of volatile contents (H, C, F, Cl, S) and H isotopic compositions with Raman spectroscopy analyses of H speciation in the glassy mesostases of EC chondrules. EC chondrule mesostases (68–830 wt. ppm H) contain much more H than chondrule silicates (5–25 wt. ppm) and are characterized by H isotopic compositions of δD = −109 ± 27‰. Hydrogen and sulfur contents are positively correlated in EC chondrule mesostases, and we commonly observed well-resolved Raman peaks at 2580 cm−1, corresponding to HS− or H2S bonding. These results illustrate that the high H abundances in EC chondrule mesostases do not result from terrestrial contamination or secondary asteroidal processes, nor were their high volatile contents inherited from chondrule precursors. Instead, they were established at high temperature during chondrule formation via interactions between Fe-poor melts and S-rich gas under extremely reducing conditions. Our data confirm that ECs contain sufficient primordial hydrogen to explain the terrestrial water budget, and likely contributed important amounts of other volatile elements such as carbon, which was fundamental to the formation of life.

In Situ Argon Isotope Analyses of Chondrule-Forming Materials in the Allende Meteorite: A Preliminary Study for 40Ar/39Ar Dating Based on Cosmogenic 39Ar

1Takeshima, Yuko,1,2Hyodo, Hironobu,3Tsujimori, Tatsuki,4Gouzu, Chitaro,
4,5,6Itaya, Tetsumaru
Minerals 13, 31 Open Access Link to Article [DOI 10.3390/min13010031]
1Graduate School of Science, Okayama University of Science, Okayama, 700-0005, Japan
2Institute of Frontier Science and Technology, Okayama University of Science, Okayama, 700-0005, Japan
3Center for Northeast Asian Studies, Tohoku University, Aoba, Sendai, 980-8576, Japan
4Hiruzen Institute for Geology & Chronology, 2-12 Nakashima, Naka-ku, Okayama, 703-8252, Japan
5Japan Geochronology Network, 2-12 Nakashima, Naka-ku, Okayama, 703-8252, Japan
6Institute of GeoHistory, Japan Geochronology Network, 1599 Susai, Akaiwa, 701-2503, Japan

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A neural network topographic correction method for the Lunar Reconnaissance Orbiter Diviner Christiansen feature map

1Ming Ma,1Chen Jingran,2,3Shengbo Chen,2Peng Lu,1Chao Sun,1Chenghao Han
Icarus (in Press) Link to Article [https://doi.org/10.1016/j.icarus.2023.115645]
1School of Surveying and Exploration Engineering, Jilin Jianzhu University, Changchun 130118, China
2School of Geo-Exploration Science and Techniques, Jilin University, Changchun 130026, China
3Center for Excellence in Comparative Planetology, Chinese Academy of Sciences, Hefei 230026, China
Copyright Elsevier

Topographic correction for lunar optical and thermal infrared remote sensing images is a challenging task. Although geometrical, photometrical or albedo-dependent correction methods have been used in an attempt to eliminate topographic effects in the initial lunar reflectance and emissivity images, these methods did not perform well on lunar steep slopes, large crater interiors or walls. In this paper, a novel neural network topographic correction (NNTC) model that was trained based on the relationships between flat (< 0.1° slope angle) and rugged pixels with similar Kaguya FeO abundance and optical maturity parameters (OMATs) (relative ratio < 0.1%) was applied to the Lunar Reconnaissance Orbiter (LRO) Diviner standard Christiansen feature (CF) image. The topographic correction accuracy is 0.03 μm, and no outliers are produced. Visual comparisons with the previous topographic corrected reflectance and emissivity images indicate that the topographic effects on various slope and aspect pixels were effectively corrected. The excavated anorthosite materials in the highland crater (such as the Jackson, Giordano Bruno and Tycho) interiors, surroundings, ejecta, and ray deposits have very similar NNTC CF values. The crater structures in maria or cryptomaria are identified more clearly. In addition, the NNTC method has the potential to be a universal topographic correction method for lunar optical and thermal infrared images, and it provides reliable data sources and a new method for space weathering correction.

Similarity assessment of lunar highland simulant (LSS-ISAC-1) for lunar habitation materials and structures

1T. Prabu,1Kasinathan Muthukkumaran,2I. Venugopal,3S. Anbazhagan
Planetary and Space Science (in Press) Link to Article [https://doi.org/10.1016/j.pss.2023.105710]
1Dept. of Civil Engineering, National Institute of Technology, Tiruchirappalli, 620015, Tamilnadu, India
2Department of Civil Engineering, M S Ramaiah Institute of Technology, Bangalore, Karnataka, India
3Faculty of Science, Director, Centre for Geoinformatics & Planetary Studies, Professor of Geology, Periyar University, Salem, 636011, Tamilnadu, India

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

Impact melt rocks from the Late Paleocene Hiawatha impact structure, northwest Greenland

1William R. HYDE,2Adam A. GARDE,2Nynke KEULEN,2Sebastian N. MALKKI,3,4Steven J. JARET,5Tod WAIGHT,6Pierre BECK,7Iain McDONALD,1Nicolaj K. LARSEN
Meteoritics & Planetary Science (in Press) Open Access Link to Article [doi: 10.1111/maps.13987]
1Globe Institute, University of Copenhagen, Copenhagen K, Denmark
2Geological Survey of Denmark and Greenland, Copenhagen K, Denmark
3Department of Earth and Planetary Sciences, American Museum of Natural History, New York, New York, USA
4Department of Physical Sciences, Kingsborough Community College, City University of New York, Brooklyn, New York, USA
5Department of Geosciences and Natural Resource Management (Geology Section), University of Copenhagen, Copenhagen K,Denmark
6Universit ́e Grenoble Alpes, CNRS, IPAG, Grenoble, France
7School of Earth and Environmental Sciences, Cardiff University, Cardiff, UK
Published by arrangement with John Wiley & Sons

Impact melt rocks formed during hypervelocity impact events are ideal forstudying impact structures. Here, we describe impact melt rock samples collected proximalto the 31 km wide 58 Ma Hiawatha impact structure, northwest Greenland, which iscompletely covered by the Greenland Ice Sheet. The melt rocks contain diagnostic shockindicators (e.g., planar deformation features [PDF] in quartz and shocked zircon) and formthree groups based on melt textures and chemistry: (i) hypocrystalline, (ii) glassy, and (iii)carbonate-based melt rocks. The exposed foreland directly in front of the structure consistsof metasedimentary successions and igneous plutons; however, the carbonate-basedimpactites indicate a mixed target sequence with a significant carbonate-rich component.Well-preserved organic material in some melt rocks indicates that North Greenland at thetime of impact was host to abundant organic material, likely a dense high-latitude temperateforest. Geochemical signatures of platinum-group elements in selected samples indicate anextraterrestrial component and support previous identification of a highly fractionated ironimpactor in glaciofluvial sand. Our results illustrate the possibility to study impact structureshidden beneath a thick ice sheet based on transported samples and this opens a new avenuefor identifying other potential impact craters in Greenland and Antarctica.