Icarus最新文献

{"title":"Mineralogical effects on organic detectability via laser desorption mass spectrometry","authors":"Madeline C. Raith ,&nbsp;Ricardo Arevalo Jr. ,&nbsp;Ashley M. Hanna ,&nbsp;Michael T. Thorpe","doi":"10.1016/j.icarus.2025.116829","DOIUrl":"10.1016/j.icarus.2025.116829","url":null,"abstract":"<div><div>The goals of current and future Mars missions include the search for biosignatures and the characterization of potentially habitable environments. Laser desorption mass spectrometry (LDMS) is capable of supporting Mars science objectives by analyzing a range of biosignatures and providing geological context for those measurements; hence the inclusion of an LDMS instrument on the ExoMars rover mission. However, LDMS techniques are sensitive to the host phase, and high-priority landings sites on Mars possess a wide range of minerals. This study explores how select minerals found on Mars, specifically those observed in Jezero crater and Oxia Planum, influence the detection of biosignatures via LDMS. Cholesterol was the target organic for this study due to its similarity to hopanoids, a class of bacterial lipids preserved in abundance in Earth's rock record. Seven Mars-relevant minerals were doped with a cholesterol-rich dilution series. This enabled the creation of calibration curves from which the limit of detection (LOD) of cholesterol adsorbed onto each mineral was determined. Of the minerals used in this study, lizardite facilitated the lowest cholesterol LOD at tens of ppmw while the other minerals had LODs up to hundreds of ppmw. Variables such as thermal conductivity, UV absorption, surface adsorption, and mineral chemistry were explored to explain the differences in LODs, but future work remains to identify the dominant influence. This work demonstrates the importance of geologic context for LDMS analyses and may be used for triaging returned samples for astrobiological studies and prioritizing targets during in-situ life detection missions.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"444 ","pages":"Article 116829"},"PeriodicalIF":3.0,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145217766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Constraining ocean and ice shell thickness on Ariel from surface geologic structures and stress mapping","authors":"Caleb Strom ,&nbsp;Tom A. Nordheim ,&nbsp;D. Alex Patthoff ,&nbsp;Sherry K. Fieber-Beyer","doi":"10.1016/j.icarus.2025.116822","DOIUrl":"10.1016/j.icarus.2025.116822","url":null,"abstract":"<div><div>The Voyager 2 flyby of Ariel revealed this moon of Uranus to be a geologically complex world. Analysis of Voyager image data has revealed Ariel to host evidence of potentially cryovolcanic features and a system of fractures and basins which could be connected to geologic resurfacing in the past 1–2 Ga. A plausible stress source for this resurfacing is tidal stress from a higher orbital eccentricity in the geologically recent past due to chaotic orbital evolution during a past episode of mean-motion resonance with the other Uranian satellites. In this study, we compare stress modeling and geologic structures on Ariel's surface to constrain the interior structure and past orbital eccentricity which would be necessary to generate sufficient stress through eccentricity tides to result in geologic resurfacing at Ariel's surface. Our results suggest that an eccentricity of e <em>≥</em> 0.04 could generate stress sufficient to cause geological resurfacing at Ariel's surface, create a stress distribution consistent with the stress distribution inferred from Ariel's surface geology, and result in a <em>∼</em> 170 km thick subsurface ocean that existed within geologically recent (1–2 Ga) time.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"444 ","pages":"Article 116822"},"PeriodicalIF":3.0,"publicationDate":"2025-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145217768","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High-altitude Martian plume is likely an ordinary twilight cloud","authors":"M.M.J. Crismani ,&nbsp;M.S. Chaffin ,&nbsp;K. Connour ,&nbsp;N.M. Schneider ,&nbsp;S. Curry ,&nbsp;J. Deighan ,&nbsp;R. Fitzpatrick ,&nbsp;S. Jain ,&nbsp;G. Liuzzi ,&nbsp;M. Slipski ,&nbsp;G.L. Villanueva","doi":"10.1016/j.icarus.2025.116823","DOIUrl":"10.1016/j.icarus.2025.116823","url":null,"abstract":"<div><div>Sánchez-Lavega et al. (2015) analyzed ground-based and space-based images of Mars that they interpreted as showing two high-altitude plumes. Their derived plume altitudes of 200 to 250 km or higher defied atmospheric processes known at the time. No supporting observations have been published in the decade since, despite ample observations by the fleet of spacecraft currently orbiting the planet. Instead, more recent observations provide strong constraints against the interpretations proposed at the time. We therefore reanalyzed the images used in that work and reviewed the methods employed by Sánchez-Lavega et al. (2015). We have identified several issues in the original data processing that may have affected the altitude determination, including surface-feature registration, black-level selection, color-image alignment, inconsistent map gridding, unknown image preprocessing, and the propagation of systematic uncertainties. Our independent analysis indicates that the features in these images are consistent with post-terminator clouds with altitudes between 50 and 100 km. Such clouds are relatively common at Mars and require no new atmospheric physics or chemistry to understand.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"444 ","pages":"Article 116823"},"PeriodicalIF":3.0,"publicationDate":"2025-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145156180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Milankovitch forcing of equilibrium ground-ice on Mars","authors":"Oded Aharonson ,&nbsp;Eran Vos ,&nbsp;Ehouarn Millour ,&nbsp;Francois Forget ,&nbsp;Norbert Schörghofer","doi":"10.1016/j.icarus.2025.116772","DOIUrl":"10.1016/j.icarus.2025.116772","url":null,"abstract":"<div><div>Exchangeable ice deposits are present today on the surface of Mars in polar caps and in the shallow subsurface in mid-latitudes. Geologic observations indicate these deposits waxed and waned in the past, at times, along with the emplacement and loss of equatorial glaciers. Here, we couple a climate model with an ice stability criterion, to self-consistently determine the distribution of the mid-latitude ground-ice deposits in diffusive equilibrium with the atmosphere, at present and under past orbital configurations. This new coupling and iteration between the short-term and long-term models improves upon past calculations that do not allow the ice table to evolve over timescales much longer than the annual climate dynamics. The model predictions for the extent of the equilibrium ice-table in the past match the latitudinal distribution of terrain softening geologic features previously mapped. At past times, thermally stable shallow ground ice is expected even in equatorial regions, in parts of Tharsis and Arabia Terra.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"444 ","pages":"Article 116772"},"PeriodicalIF":3.0,"publicationDate":"2025-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145119734","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Erratum to ‘Rock suites of Endeavour crater, Mars: Comparing Perseverance Valley, Spirit of St. Louis, and Marathon Valley’ Icarus 442C (2025) 116752","authors":"Michael C. Bouchard,&nbsp;Bradley L. Jolliff","doi":"10.1016/j.icarus.2025.116805","DOIUrl":"10.1016/j.icarus.2025.116805","url":null,"abstract":"","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"444 ","pages":"Article 116805"},"PeriodicalIF":3.0,"publicationDate":"2025-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145097714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mineral quantitative inversion based on in-situ spectral observations from Yutu-2: Anomalous sample origin and mineral composition variations on the Rover's path","authors":"Kecheng Du ,&nbsp;Sicong Liu ,&nbsp;Xiaohua Tong ,&nbsp;Qian Du ,&nbsp;Huan Xie ,&nbsp;Yongjiu Feng ,&nbsp;Yanmin Jin","doi":"10.1016/j.icarus.2025.116821","DOIUrl":"10.1016/j.icarus.2025.116821","url":null,"abstract":"<div><div>In January 2019, China's Chang'e-4 (CE-4) spacecraft successfully landed in Von Kármán crater on the farside of the Moon. During nearly six years of operation until November 2024, the Visible and Near-infrared Image Spectrometer (VNIS) onboard the Yutu-2 rover acquired in-situ spectral data along an approximately 1600 m traverse path, offering critical opportunities to investigate subtle mineralogical variations within the patrol region. In this study, we analyzed these spectral data using a sparse spectral decomposition method with TiO₂ constraints to quantitatively estimate the abundances of six lunar minerals, including high‑calcium pyroxene, low-calcium pyroxene, olivine, plagioclase, ilmenite and agglutinate/glass. We further examined the mineralogical properties of regolith and rocks in Yutu-2's patrol area to identify trends and correlations in compositional variations. By comparing results with Kaguya Multiband Imager data products, we identified a gradual decreasing spatial distribution in plagioclase abundance along the traverse path, likely attributable to ejecta from the Zhinyu crater. Furthermore, analysis of Moon Mineral Mapper (M³) data revealed samples with similar spectral characteristics near Zhinyu crater, supporting this hypothesis. Additionally, the impact of secondary impact craters on local regions was qualitatively and quantitatively assessed using VNIS spectral features and agglutinate/glass abundance. These findings enhance understanding of the complex origin and evolution of materials at the CE-4 landing site region.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"444 ","pages":"Article 116821"},"PeriodicalIF":3.0,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145119733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Condensation of major and trace elements in dust-rich environments","authors":"Marwane Mokhtari,&nbsp;Bernard Bourdon","doi":"10.1016/j.icarus.2025.116801","DOIUrl":"10.1016/j.icarus.2025.116801","url":null,"abstract":"<div><div>Recent astronomical observations have shown that dust can get locally concentrated in protoplanetary disks, forming ring structures. The thermal processing of such regions could lead to dust evaporation and local enrichment of the solar gas in condensable elements. Previous studies focusing on major element behavior have shown that condensation of such dust-enriched gas could lead to the formation of a silicate melt with compositions resembling that of chondrules. However, previous studies focusing on dust-enriched environments were restricted to a limited set of elements. To study the mineralogical and chemical composition of condensates in these conditions, we have performed equilibrium calculations using the FactSage™ software for a dust-enriched solar gas. The calculations were done with dust-enrichment factors of 1 (solar composition), 10 and 100 at pressures ranging between 10⁻⁶ bar and 10⁻³ bar, for a CI-chondrite dust and a H-chondrite dust. The trace element condensation was accurately modelled with newly calculated activity coefficients in different solid and melt solutions. The available gas phase database was completed with new trace element species that are important to consider in oxidized conditions. The mineralogical sequence, melt composition and condensation temperature for all condensable elements were then quantified.</div><div>Our calculations show that the iron contents of olivine in equilibrium with a gas that is x100 enriched in CI-dust is consistent with that of amoeboid olivine aggregates and chondrules. Furthermore, our estimated temperature at which fayalite can form in these conditions is higher than what was previously proposed, enabling diffusion and homogenization of iron in olivine. The calculated composition of refractory metals for a x10 and x100 CI-dust enriched gas at 10⁻⁴ bar is consistent with the measured compositions of refractory metal nuggets. The possibility for these grains to have formed in an H₂O ice-enriched gas can be ruled out as the calculated fractionation patterns in this case did not match the observed compositions.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"444 ","pages":"Article 116801"},"PeriodicalIF":3.0,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145268237","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A full-atmosphere model of Jupiter","authors":"Antonín Knížek ,&nbsp;Paul B. Rimmer ,&nbsp;Martin Ferus","doi":"10.1016/j.icarus.2025.116806","DOIUrl":"10.1016/j.icarus.2025.116806","url":null,"abstract":"<div><div>This paper presents a combined 1D photochemical–thermochemical kinetics model of Jupiter’s deeper atmosphere, troposphere and stratosphere. The model covers atmospheric pressure range from <span><math><mrow><mn>1</mn><mo>.</mo><mn>1</mn><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>3</mn></mrow></msup></mrow></math></span> bar to <span><math><mrow><mn>7</mn><mo>.</mo><mn>4</mn><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>11</mn></mrow></msup></mrow></math></span> bar and is the first model that incorporates sulfur chemistry when spanning an atmospheric region of this extent. This model incorporates a new version of the STAND reaction network with updated NH₄SH chemistry, and updated Antoine equation parameters for NH₄SH and H₂S. Validation against current models of Jupiter’s atmosphere as well as recent observational data shows that our model successfully describes Jupiter’s main observed chemical features. Since one of the focuses of the model is the chemistry on nitrogen, it correctly predicts the formation of a mixed NH₃-NH₄SH cloud layer between 0.1 and 1 bar. It also describes the chemistry of HCN throughout the atmosphere and discovers a region in the stratosphere between <span><math><mrow><mn>1</mn><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>6</mn></mrow></msup></mrow></math></span> and <span><math><mrow><mn>6</mn><mo>.</mo><mn>76</mn><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>8</mn></mrow></msup></mrow></math></span> bar, where HCN forms through radical chemistry with maximum mixing ratio 33 ppb at <span><math><mrow><mn>2</mn><mo>.</mo><mn>94</mn><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>7</mn></mrow></msup></mrow></math></span> bar – a prediction testable by observations. At the same time, our model predicts a quenched N₂ mixing ratio 490 ppm up to 10⁻⁶ bar. The model therefore successfully bridges the gap between existing models of separate regions of Jupiter’s atmosphere and makes new testable predictions of several chemical species.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"444 ","pages":"Article 116806"},"PeriodicalIF":3.0,"publicationDate":"2025-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145156179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Detailed topographic and geomorphological analyses of Chang'e-6 landing area","authors":"Yexin Wang ,&nbsp;Chenxu Zhao ,&nbsp;Biao Wang ,&nbsp;Bin Xie ,&nbsp;Kaichang Di ,&nbsp;Hong Zhang ,&nbsp;Xiangjin Deng ,&nbsp;Wai Chung Liu ,&nbsp;Yifan Zhang ,&nbsp;Bin Liu ,&nbsp;Ruiqing Sheng ,&nbsp;Yang Zhao ,&nbsp;Shujuan Sun ,&nbsp;Li Li ,&nbsp;Sheng Gou ,&nbsp;Zongyu Yue","doi":"10.1016/j.icarus.2025.116820","DOIUrl":"10.1016/j.icarus.2025.116820","url":null,"abstract":"<div><div>China's Chang'e-6 (CE-6) mission landed successfully in the Apollo basin inside the South Pole-Aitken basin, marking the first lunar farside sample return mission. Prior to the landing of the probe, detailed analyses of the topography and geomorphology of the target landing area are necessary to ensure a safety landing. This paper presents the approaches and results of topographic and geomorphological analyses for the 28 km × 6 km pre-selected landing area of the CE-6 mission. First, a seamless digital orthophoto map (DOM) of the area with resolution of 1 m/pixel is produced using the Lunar Reconnaissance Orbiter Narrow Angle Camera images. Second, a 1 m/pixel resolution digital elevation model (DEM) of this area is generated based on the deep learning terrain reconstruction method, and topographic analysis is conducted based on the DEM. Third, on the basis of the DOM and DEM data, typical geomorphological features within the pre-selected landing area, such as craters and rocks, are extracted and their properties are analyzed. The above topographic data and analyses results directly supported detailed landing site selection and safe landing for the CE-6 mission, and provide fundamental information for further scientific investigations of the landing area and the collected samples.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"444 ","pages":"Article 116820"},"PeriodicalIF":3.0,"publicationDate":"2025-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145156178","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Noble gas fractionation predictions for high speed sampling in the upper atmosphere of Venus","authors":"Arnaud Borner ,&nbsp;Michael A. Gallis ,&nbsp;Rita Parai ,&nbsp;Guillaume Avice ,&nbsp;Mihail P. Petkov ,&nbsp;Krishnan Swaminathan-Gopalan ,&nbsp;Christophe Sotin ,&nbsp;Jason Rabinovitch","doi":"10.1016/j.icarus.2025.116800","DOIUrl":"10.1016/j.icarus.2025.116800","url":null,"abstract":"<div><div>Venus, our neighboring planet, is an open-air laboratory that can be used to study why Earth and Venus evolved in such different ways and even to better understand exoplanets. Noble gases in planetary atmospheres are tracers of their geophysical evolution, and measuring the elemental and isotopic composition of noble gases in the Venus atmosphere informs us about the origin and evolution of the entire planet. In this work we describe a new mission concept, Venus ATMOSpheric - Sample Return (VATMOS-SR), that would return gas samples from the upper atmosphere of Venus to Earth for scientific analysis. This could be the first sample return mission for an extraterrestrial atmosphere. To ensure it is possible to relate the composition of the sampled gases (acquired when the spacecraft is traveling <span><math><mrow><mo>&gt;</mo><mn>10</mn></mrow></math></span> km/s) to the freestream atmospheric composition, large-scale numerical simulations are employed to model the flow into and through the sampling system. In particular, an emphasis is placed on quantifying noble gas elemental and isotopic fractionation that occurs during the sample acquisition and transfer process, to determine how measured isotopic ratios of noble gases in the sample would compare to the actual isotopic ratios in the Venusian atmosphere. We find that lighter noble gases are depleted after they are sampled compared to the freestream conditions, and heavier ones are enriched, due to the high pressure gradients present in the flowfield. We also observe that lighter noble gases are more affected than heavier ones by changes in the freestream conditions. Finally, we observe that, in general, the numerical parameters do not have a major impact on the observed fractionation. We do, however, note that the freestream velocity and density have a major impact on fractionation, and do need to be precisely known to properly reconstruct the fractionation in the sampling system. We demonstrate that the sample fractionation can be predicted with numerical simulations, and believe that VATMOS-SR, which could be the first mission to bring back samples from another planet, could answer key scientific questions related to understanding the evolution of Venus.</div></div>","PeriodicalId":13199,"journal":{"name":"Icarus","volume":"444 ","pages":"Article 116800"},"PeriodicalIF":3.0,"publicationDate":"2025-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145119706","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}