npj space explorationPub Date : 2026-01-01Epub Date: 2026-01-27DOI: 10.1038/s44453-025-00018-5
Taylor P Davis, Laurence A J Garvie, Christian G Hoover
{"title":"Phase-specific nanoscale mechanics of anhydrous astromaterials and implications for larger-scale strength.","authors":"Taylor P Davis, Laurence A J Garvie, Christian G Hoover","doi":"10.1038/s44453-025-00018-5","DOIUrl":"10.1038/s44453-025-00018-5","url":null,"abstract":"<p><p>The mechanical behavior of heterogeneous astromaterials is strongly influenced by their dominant mineral phases. Quantifying their mechanical properties is essential for modeling asteroid deflection, designing sample return systems, and planning in-situ resource utilization. Yet, data for the major mineral phases that comprise a large fraction of near-Earth objects (NEOs) remains scarce. Here, depth-sensing nanoindentation is used to measure nanoscale hardness (<i>H</i>), modulus (<i>M</i>), and ductility (<i>M</i>/<i>H</i>) for the primary phases in a representative stony meteorite. Targeted phases include anhydrous silicates, oxides, sulfides, and Fe-Ni metals. The Ashby plot of <i>M</i> versus <i>H</i> shows that metals and silicates are widely separated in property space. A rule-of-mixtures approach is applied to estimate upper bounds on bulk modulus, linking mineral-scale measurements to bulk mechanical behavior. These results provide new insights into the nanoscale mechanics of complex extraterrestrial materials and establish a foundation for connecting properties across scales.</p>","PeriodicalId":521231,"journal":{"name":"npj space exploration","volume":"2 1","pages":"5"},"PeriodicalIF":0.0,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12863664/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146115530","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
npj space explorationPub Date : 2026-01-01Epub Date: 2026-06-12DOI: 10.1038/s44453-026-00045-w
Seamus L Anderson, Prabal Saxena, Philip T Metzger
{"title":"Mitigating plume surface interactions using lunar craters.","authors":"Seamus L Anderson, Prabal Saxena, Philip T Metzger","doi":"10.1038/s44453-026-00045-w","DOIUrl":"10.1038/s44453-026-00045-w","url":null,"abstract":"<p><p>Launching and landing spacecraft on the lunar surface mobilizes regolith at high velocities which will likely cause damage to nearby objects and infrastructure, a phenomenon known as plume surface interactions (PSIs) that must be mitigated for sustainable lunar surface exploration. While some mitigation strategies prescribe the construction of walls and landing pads using locally sourced regolith and additive manufacturing techniques, cheaper and more immediately available approaches may be required. We introduce a novel concept that uses small lunar craters (<1.5 km) as unprepared landing sites to mitigate the hazards posed by PSIs. We simulated the ballistic trajectories of regolith grains ejected by PSIs from the centers of 238 lunar craters and find that many could completely shield nearby areas from ejected regolith, with some of these protected \"umbrella zones\" being large enough to host either a 16 m-tall Blue Moon Mk. 2 lander or a lunar outpost. These examined craters are also conducive to safe landings as they retain sufficiently large and flat crater floors, as well as crater walls that are traversable by the Artemis program's proposed Lunar Terrain Vehicle. However, much work remains for this approach to be fully relied upon as a mitigation strategy.</p>","PeriodicalId":521231,"journal":{"name":"npj space exploration","volume":"2 1","pages":"28"},"PeriodicalIF":0.0,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13263143/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148255504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
npj space explorationPub Date : 2026-01-01Epub Date: 2026-04-02DOI: 10.1038/s44453-026-00031-2
Bartosz Pieterek, Thomas J Jones
{"title":"Recent explosive lava-water interaction in Tharsis, Mars.","authors":"Bartosz Pieterek, Thomas J Jones","doi":"10.1038/s44453-026-00031-2","DOIUrl":"10.1038/s44453-026-00031-2","url":null,"abstract":"<p><p>The spatiotemporal distribution of water on Mars is fundamental to understanding the planet's evolution. Comprehensive integration and analysis of high-resolution remotely sensed datasets have enabled the investigation of previously uninterpreted small-scale volcanic landforms that imply the involvement of water during formation. Although volcanism has played a dominant role in shaping the Martian surface, irrespective of the physical state of water, there is little evidence of magma-water or lava-water interactions, especially in young, late Amazonian-aged volcanic provinces. Here, by combining surface imagery with topographic data and spectral analyses, we report the presence of rootless volcanic cones formed by explosive lava-water interaction during the late Amazonian (<215 Ma). They are found adjacent to Ascraeus Mons in Tharsis and are associated with spectrally identified hydrated minerals, most likely sulfates, indicating past hydrothermal circulation potentially sustained by lava-water interactions. We contend that these young, small landforms, formed through phreatomagmatic eruptions, can help reconstruct Martian paleoclimate, identifying water ice zones, and should be considered prime targets in the future search for life, as they fulfill key habitability criteria.</p>","PeriodicalId":521231,"journal":{"name":"npj space exploration","volume":"2 1","pages":"15"},"PeriodicalIF":0.0,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13046473/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147625461","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
npj space explorationPub Date : 2026-01-01Epub Date: 2026-07-03DOI: 10.1038/s44453-026-00048-7
Yaozhu Li, Szilvia Kalácska, Phil J A McCausland, Roberta L Flemming, Callum J Hetherington, Bo Zhao, Can Yildirim, Carsten Detlefs
{"title":"Remanent crustal strain on Mars in non-poikilitic olivine of NWA 7721.","authors":"Yaozhu Li, Szilvia Kalácska, Phil J A McCausland, Roberta L Flemming, Callum J Hetherington, Bo Zhao, Can Yildirim, Carsten Detlefs","doi":"10.1038/s44453-026-00048-7","DOIUrl":"10.1038/s44453-026-00048-7","url":null,"abstract":"<p><p>We present a multiscale, non-destructive analysis of non-poikilitic olivine in the shergottite NWA 7721 using dark-field X-ray microscopy, electron backscatter diffraction, and 2D micro-X-ray diffraction. We report striking bimodal microstructures within a single olivine crystal: fine Type 1 subgrains (around 5 μm), weakly oriented, and nearly strain-free; coarser Type 2 subgrains (>15 μm), aligned, and strongly strained. Layered DFXM data reveal slip-band features in Type 2 that are absent in Type 1. This bimodal microstructure, not observed in other Martian meteorites, including the paired NWA 1950 and ALH A77005, points to a heterogeneous response to impact at the crystallographic scale. We interpret Type 1 as shock-assisted recrystallites and Type 2 as relic partitioned from a highly deformed parental grain with a pre-existing fabric. The subsequent shock wave imposed a rapid load-release cycle that generated heterogeneous deformation within the crystal. Highly strained regions underwent recrystallization to form Type 1 subgrains, whereas less-strained domains retained deformation structures as Type 2. Grain-growth constraints limit the post-shock heating to ≈2.3 s, consistent with rapid quenching. Together, these observations illustrate a dynamic Martian crustal activity in the Late Amazonian and demonstrate DFXM, combined with EBSD and micro-XRD, as a promising tool for resolving complex fabrics in 3D.</p>","PeriodicalId":521231,"journal":{"name":"npj space exploration","volume":"2 1","pages":"30"},"PeriodicalIF":0.0,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13331735/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148393153","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
npj space explorationPub Date : 2026-01-01Epub Date: 2026-10-09DOI: 10.1038/s44453-026-00057-6
Connor J MacRobbie, Sayan Saha, Omer Syed, Spencer Dionisio, Kyle MacRobbie, John Z Wen, Madelyn MacRobbie
{"title":"Lunar regolith simulant milling under lunar gravity conditions.","authors":"Connor J MacRobbie, Sayan Saha, Omer Syed, Spencer Dionisio, Kyle MacRobbie, John Z Wen, Madelyn MacRobbie","doi":"10.1038/s44453-026-00057-6","DOIUrl":"https://doi.org/10.1038/s44453-026-00057-6","url":null,"abstract":"<p><p>There is a significant gap in lunar planetary research regarding the beneficiation of lunar regolith under representative conditions. Decreasing regolith particle size can have advantageous effects for metal extraction, oxygen extraction, manufacturing, and energy harvesting. However, particle size reduction methods have not yet been studied in reduced gravity conditions. In this work, we present a novel experiment consisting of three milling methods built to decrease regolith simulant particle size in lunar gravity conditions using a parabolic flight platform. Physical properties such as the particle size and morphology of lunar regolith simulant are evaluated before and after milling to quantify the ability for each milling device to reduce the size of lunar regolith simulant. The samples milled under lunar gravity conditions are quantified against control samples milled on Earth for the same duration to evaluate the effects of gravity on the milling processes. First order rate equations are fit to the particle size reduction, and non-dimensional analyses demonstrates the key controlling parameters of the particle sizes reduction rates and limits include the device geometry, applied stress, gravity magnitude, and cohesion between particles. The results of this study will be used to inform the design of future lunar regolith beneficiation technologies.</p>","PeriodicalId":521231,"journal":{"name":"npj space exploration","volume":"2 1","pages":"39"},"PeriodicalIF":0.0,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13652733/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149170870","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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