Journal of Geophysical Research: Planets最新文献

{"title":"FeO and TiO2 Maps of the Lunar Polar Regions Derived From the Clementine Data","authors":"Denggao Qiu,&nbsp;Wencong Chen,&nbsp;Jianguo Yan,&nbsp;Sihai Yi","doi":"10.1029/2024JE008753","DOIUrl":"https://doi.org/10.1029/2024JE008753","url":null,"abstract":"<p>Chang’E-6 successfully completed the return of samples from the South Pole-Aitken (SPA) basin on the Moon, and future Chang’E-7 and Artemis missions will continue to focus on the lunar south polar region. FeO and TiO₂ are the primary chemical components of the lunar surface, and determining their contents in the south polar region is essential for investigating the geology and volcanism of this region. This work remapped the global FeO and TiO₂ content using Clementine data combined with updated lunar sample measurements. The new models for FeO and TiO₂ achieve determination coefficients (R²) of 0.921 and 0.817, and root mean square errors (RMSE) of 1.38 wt.% and 1.17 wt.%, respectively. The addition of sample measurements from Chang’E-3 and Chang’E-5 has resulted in higher estimates for FeO content in the Procellarum KREEP Terrane (PKT) and the SPA, as well as lower estimates for TiO₂ content in the maria. Furthermore, we present the Chang’E-6 landing zone in the PKT to illustrate the geological implications of the new oxide content maps. Estimates of surface FeO and TiO₂ content at the Chang’E-6 sampling site are close to recent sample measurements and are consistent with the characteristics of the young maria unit in the landing zone. Our results provide valuable information on FeO and TiO₂ content in the lunar south polar region, which will aid in the future analysis of Chang’E-6 samples and contribute to geological investigations in the region.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 2","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143380176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring the Jau Crater Cluster, Gale Crater, Mars","authors":"J. A. Grant,&nbsp;M. E. Hoffman,&nbsp;H. E. Newsom posthumously,&nbsp;T. Kubacki,&nbsp;C. Juarez,&nbsp;N. Moore,&nbsp;S. A. Wilson,&nbsp;T. J. Parker","doi":"10.1029/2024JE008763","DOIUrl":"https://doi.org/10.1029/2024JE008763","url":null,"abstract":"<p>The Jau crater cluster on the north flank of Mt. Sharp in the Gale crater consists of 20–30 simultaneously formed impact structures. The craters are ∼2 to ∼25 m across (generally increasing in size from the ESE to WNW). Using Digital Terrain Models derived from orbital and rover orthomosaics of two of the larger craters, we evaluated the amount and processes of degradation based upon current versus expected original crater morphology. We conclude that the craters in the cluster are the result of a fragmenting primary impactor and that predominantly aeolian degradation at these two craters is responsible for ∼1–2 m wall back-wasting, 10s of cm of infilling by aeolian drift, and 20–40 cm rim lowering. Other craters in the cluster experienced similar degradation whose expression varied according to crater size: smaller-scale morphology at smaller craters is more modified by a given amount of erosion. Prevailing winds erode the downhill, NNE side of the craters more though raised rims persist at the larger craters. An estimated vertical erosion rate of 0.1 m/Myr and a horizontal erosion rate of several m/Myr predicted by others appear most consistent with the Jau crater morphology and setting relative to erosion estimates for elsewhere in Gale crater and other Mars landing sites. Factoring in uncertainties in our estimates, these rates are broadly consistent with the scale of erosion inferred for the evolution of larger, older features on Mt. Sharp and suggest that the cluster-forming impact occurred one to a few and less than ∼5 Ma.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 2","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143380011","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Channelized Thermal Emission, Promethean-Type Jets and Surface Changes on Io From Juno Stellar Reference Unit Imagery","authors":"Heidi N. Becker,&nbsp;Paul M. Schenk,&nbsp;Rosaly M. C. Lopes,&nbsp;Martin J. Brennan,&nbsp;Meghan M. Florence,&nbsp;Alessandro Mura,&nbsp;Federico Tosi,&nbsp;Jonathan I. Lunine,&nbsp;James W. Alexander,&nbsp;Michael A. Ravine,&nbsp;Candice J. Hansen,&nbsp;Scott J. Bolton","doi":"10.1029/2024JE008744","DOIUrl":"https://doi.org/10.1029/2024JE008744","url":null,"abstract":"<p>During Juno's close flybys of Io in 2023 and 2024, its low-light sensitive Stellar Reference Unit (SRU) was used to conduct a high-resolution visible wavelength (450–1,100 nm) imaging campaign under Jupiter-shine illumination. The SRU acquired Juno's highest resolution image of Io's surface (895–1,230 m/pixel) in December 2023 at a high Jupiter-shine phase angle of ∼110°. The image reveals structural changes in Zal Patera since Galileo (1999–2000) and multiple forms of active volcanism within the Zal Montes-Patera complex, including Promethean-type jets at the flow fronts of a new Zal Patera flow branch. The SRU's sensitivity at redder wavelengths enabled the detection of thermal emission from an active lava channel to the west of South Zal Mons. An additional emission signature is seen at the base of a vertical mountain fracture on the western flank of South Zal Mons, suggestive of a tectonically influenced source vent. Indeed, the SRU's observations in this region suggest a close relationship between mountains and volcanism on Io. The SRU data also provide the first high-resolution view of the geomorphology of the eruptive center Tonatiuh, revealing it to be a compound Promethean-style flow field. SRU imagery from subsequent flybys in February and April 2024 suggest high volcanic activity in the Lei-zi Fluctus region and show increased expansion of the large Masubi flow field in Io's southern hemisphere. Now containing ∼1,600 km of lava flows, Masubi is the longest currently active flow field in the solar system.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 2","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JE008744","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143370076","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Widespread Occurrence of Lava Lakes on Io Observed From Juno","authors":"Alessandro Mura,&nbsp;Federico Tosi,&nbsp;Francesca Zambon,&nbsp;Rosaly M. C. Lopes,&nbsp;Peter J. Mouginis-Mark,&nbsp;Jani Radebaugh,&nbsp;Alberto Adriani,&nbsp;Scott Bolton,&nbsp;Julie Rathbun,&nbsp;Andrea Cicchetti,&nbsp;Davide Grassi,&nbsp;Raffaella Noschese,&nbsp;Giuseppe Piccioni,&nbsp;Christina Plainaki,&nbsp;Roberto Sordini,&nbsp;Giuseppe Sindoni","doi":"10.1029/2024JE008723","DOIUrl":"https://doi.org/10.1029/2024JE008723","url":null,"abstract":"<p>We report recent observations of lava lakes within patera on Io made by the JIRAM (Jovian InfraRed Auroral Mapper) imager on board the Juno spacecraft, taken during close observations that occurred during the extended mission. At least 40 lava lakes have been identified from JIRAM observations. The majority (&gt;50%) of paterae have elevated thermal signatures when imaged at sufficiently high spatial resolution (a few km/pixel), implying that lava lakes are ubiquitous on Io. The annular width of the spattering region around the margins, a characteristic of lava lakes, is of the order of few meters to tens of meters, while the diameter of the observed lava lakes ranges from 10 to 100 km. The thickness of the crust in the center of some lava lakes is of the order of 5–10 m; we estimate that this crust is a few years old. Also, the bulk of the thermal emission comes from the much larger crust and not from the smaller exposed lava, so the total power output cannot be calculated from the 5-μm radiance alone. Eight of the proposed lava lakes have never been reported previously as active hotspots.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 2","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JE008723","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143248702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Collection and In Situ Analyses of Regolith Samples by the Mars 2020 Rover: Implications for Their Formation and Alteration History","authors":"E. M. Hausrath,&nbsp;R. Sullivan,&nbsp;Y. Goreva,&nbsp;M. P. Zorzano,&nbsp;A. Vaughan,&nbsp;A. Cousin,&nbsp;S. Siljeström,&nbsp;S. Sharma,&nbsp;A. O. Shumway,&nbsp;T. Kizovski,&nbsp;S. J. VanBommel,&nbsp;M. Tice,&nbsp;A. Knight,&nbsp;G. Martinez,&nbsp;A. Vicente-Retortillo,&nbsp;L. Mandon,&nbsp;C. T. Adcock,&nbsp;J. M. Madariaga,&nbsp;I. Población,&nbsp;J. R. Johnson,&nbsp;J. Lasue,&nbsp;O. Gasnault,&nbsp;N. Randazzo,&nbsp;E. L. Cardarelli,&nbsp;R. Kronyak,&nbsp;A. Bechtold,&nbsp;G. Paar,&nbsp;A. Udry,&nbsp;O. Forni,&nbsp;C. C. Bedford,&nbsp;N. A. Carman,&nbsp;J. F. Bell III,&nbsp;K. Benison,&nbsp;T. Bosak,&nbsp;A. Brown,&nbsp;A. Broz,&nbsp;F. Calef,&nbsp;B. C. Clark,&nbsp;E. Cloutis,&nbsp;A. D. Czaja,&nbsp;T. Fornaro,&nbsp;T. Fouchet,&nbsp;M. Golombek,&nbsp;F. Gómez,&nbsp;C. D. K. Herd,&nbsp;K. Herkenhoff,&nbsp;R. S. Jakubek,&nbsp;L. Jandura,&nbsp;J. Martinez-Frias,&nbsp;L. E. Mayhew,&nbsp;P.-Y. Meslin,&nbsp;C. E. Newman,&nbsp;J. I. Núñez,&nbsp;F. Poulet,&nbsp;C. Royer,&nbsp;P. Russell,&nbsp;M. A. Sephton,&nbsp;S. K. Sharma,&nbsp;D. Shuster,&nbsp;J. I. Simon,&nbsp;I. Tirona,&nbsp;R. C. Wiens,&nbsp;B. P. Weiss,&nbsp;A. J. Williams,&nbsp;K. Williford,&nbsp;Z. U. Wolf,&nbsp;the Regolith Working Group","doi":"10.1029/2023JE008046","DOIUrl":"https://doi.org/10.1029/2023JE008046","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <p>The <i>Perseverance</i> rover has sampled mm-size lithic fragments containing olivine likely from at least two source regions from the surface of an inactive megaripple surface, and fine-grained material from the surface and to a depth of ∼4–6 cm. Some of the mm-size grains lack a coherent diffraction pattern measured by PIXL, consistent with the presence of poorly ordered secondary phases that have been altered. Analysis of these materials on Earth will allow examination of materials that have experienced aqueous, potentially habitable environments that could contain biosignatures. Fluorescence of three different patterns was detected, consistent with inorganic emissions from silica defects or rare earth elements in certain mineral phases, although organic origin cannot be excluded. Analysis of Autofocus Context Imager and Wide Angle Topographic Sensor for Operations and eNgineering images of the subsurface material and MEDA thermal inertia measurements indicate average grain sizes of ∼125 and ∼150 μm, respectively, for the bulk material within the megaripple. The fine-grained material in the sampling location indicates chemical compositions similar to previously proposed global components as well as airfall dust. In situ and associated atmospheric measurements provide evidence of recent processes likely including water vapor in soil crust formation. The sampled material will therefore help elucidate the formation of Martian soils; current surface-atmosphere interactions; the composition, shape, and size distribution of dust grains valuable for studies of past and present Martian climate and for assessing potential health and other risks to human missions; and ancient, aqueously altered environments that could have been habitable, and, if Mars contained life, possibly contain biosignatures.</p>\u0000 </section>\u0000 </div>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 2","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023JE008046","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143362545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Diurnal and Seasonal Variations of Gravity Waves in the Lower Atmosphere of Mars as Observed by InSight","authors":"J. Hernández-Bernal,&nbsp;A. Spiga,&nbsp;A. Chatain,&nbsp;J. Pla-Garcia,&nbsp;D. Banfield","doi":"10.1029/2024JE008746","DOIUrl":"https://doi.org/10.1029/2024JE008746","url":null,"abstract":"<p>We investigate Gravity Waves (GWs) in the lower atmosphere of Mars based on pressure timeseries acquired by the InSight lander. We compile a climatology showing that most GW activity detected at the InSight landing site takes place after the sunrise and sunset; they are almost absent during the aphelion season, and more prominent around the equinoxes, with variations during dust events and interannual variations. We find GWs with coherent phases in different sols, and a previously unnoticed coincidence of GW activity with those moments in which the diurnal cycle (of tidal origin) exhibits the fastest increases in absolute pressure. We explore the possibility that some of these GWs might actually be high-order harmonics of thermal tides transiently interfering constructively to produce relevant meteorological patterns, and discuss other interpretations based on wind patterns. The so-called Terminator Waves observed on Earth might also explain some of our observations.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 2","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JE008746","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143110763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact Gardening Affects the Composition of Chang'e-5 Lunar Soils","authors":"Yanze Su,&nbsp;Luyuan Xu,&nbsp;Meng-Hua Zhu","doi":"10.1029/2024JE008501","DOIUrl":"https://doi.org/10.1029/2024JE008501","url":null,"abstract":"<p>The composition of lunar samples sheds light on the Moon's evolutional history. Analyses of Chang'e-5 (CE-5) lunar soils showed &lt;5% of foreign materials, significantly less than numerical predictions (∼10%). To address this inconsistency, we simulated the impact gardening process, accounting for distal ejecta, and tracked the compositional changes in the top 1 m layer at CE-5 landing area over time. Our results show that impact gardening brings deeper local materials to the surface, leading to a mixture that reduces the distal ejecta proportion within the top 1 m layer from which the soils were collected. After 2.0 Gyr of impact gardening, most materials of the top 1 m layer originate from the upper layer (depth &lt;30 m) of local basalts, with distal ejecta as a minor component (∼2.7 vol.%), consistent with CE-5 soils analyses. Our results emphasize the profound influence of impact gardening on the composition of lunar soils.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 2","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143121226","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatiotemporal Variability of Saturn's Zonal Winds Observed by Cassini","authors":"Xinyue Wang,&nbsp;Liming Li,&nbsp;Larry Guan,&nbsp;Xun Jiang,&nbsp;Patrick M. Fry,&nbsp;Ulyana A. Dyudina,&nbsp;Leigh N. Fletcher,&nbsp;Enrique García-Melendo,&nbsp;Ricardo Hueso,&nbsp;Raúl Morales-Juberías,&nbsp;Agustin Sánchez-Lavega,&nbsp;Amy A. Simon","doi":"10.1029/2024JE008515","DOIUrl":"https://doi.org/10.1029/2024JE008515","url":null,"abstract":"<p>The strong zonal winds on giant planets are among the most interesting phenomena in our solar system. Observations recorded by the Composite Infrared Spectrometer (CIRS), the Imaging Science Subsystem (ISS), and the Visual and Infrared Mapping Spectrometer (VIMS) on the Cassini spacecraft are utilized to investigate spatiotemporal variations in Saturn's zonal winds. A general thermal wind equation works for investigating the vertical structure of zonal winds at all latitudes, but it has integration gaps near the equator caused by the cylindrical integration path. Here, we develop an algorithm to address this limitation, which is validated by the observed zonal winds. The algorithm is combined with the CIRS-retrieved temperature and the ISS-measured winds to generate a complete picture of the vertical structure of Saturn's zonal winds for the upper troposphere (i.e., 50–500 mbar), which suggests that the equatorial zonal winds have complicated vertical structures. The zonal winds from 10°S to 10°N initially decrease with altitude and then increase. Additionally, the intense narrow equatorial jet between 3°S and 3°N widens with altitude. The zonal winds are further used to examine the atmospheric stability, which implies some unstable regions. Finally, the analysis of Cassini multi-instrument observations reveals different temporal behaviors of zonal winds in the vertical direction, which suggests that seasonally varying solar flux is one of the drivers of temporal variations in zonal winds.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143119912","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Shallow Water Ice Detection From SHARAD Data in Central Utopia Planitia, Mars","authors":"Xiaoting Xu,&nbsp;Yi Xu,&nbsp;Zhuo Han,&nbsp;HonKuan Wong,&nbsp;Xu Meng,&nbsp;Yu-Yan Sara Zhao,&nbsp;Roberto Bugiolacchi,&nbsp;Shuanggen Jin","doi":"10.1029/2023JE008145","DOIUrl":"https://doi.org/10.1029/2023JE008145","url":null,"abstract":"<p>One of the key scientific goals of China's first Mars mission Tianwen-1 is to search for ground ice. This study focuses on investigating potential water ice reservoirs in the vicinity of the landing site of the Zhurong rover to provide geological context and references for data interpretation. Our study area is centered on Utopia Planitia (UP), where Shallow Radar onboard the Mars Reconnaissance Orbiter (SHARAD) previously detected subsurface echoes that could be interpreted as ice deposits. Based on the SHARAD data, we have estimated the thickness, dielectric properties, and possible material composition of the surface deposition layer. The inferred water ice volume content ranges from approximately 55%–85%, which is consistent with deposits found on the western edge of UP. Based on morphological features and radar data products, we interpret the detected sediment layer as the latitude-dependent mantle (LDM). We have conducted a comprehensive analysis of the distribution and morphology of various periglacial landforms, including Decameter-scale Rimmed Depressions (DRDs), polygonal landforms, and scalloped depressions on the surface of UP. The implications for the level of degradation are discussed. The radar results provide evidence that DRDs have formed as a result of the degradation of the LDM layer. Additionally, our statistical analysis of concentric crater humps (CCH) linked to subsurface pure glacial ice suggests the possible presence of an icy layer that may be as thick as a kilometer beneath the LDM unit.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143119913","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Limited Influence of Hydrogen on the Sound Velocity of the Martian Core: Constraints From First-Principles Molecular Dynamics Simulations of Fe-S-H Liquids","authors":"Tao Liu,&nbsp;Zhicheng Jing","doi":"10.1029/2024JE008552","DOIUrl":"https://doi.org/10.1029/2024JE008552","url":null,"abstract":"<p>Recent seismic observations from the InSight mission have provided new constraints to the structure, density, and sound velocity of the martian core. Despite these advancements, the precise compositional makeup of the martian core remains largely uncertain, partly due to the poorly constrained equations of state for Fe-light element alloying liquids. Here we performed first-principles molecular dynamics simulations of Fe-S and Fe-S-H liquids under pressures of 16–58 GPa and temperatures of 1,700–3,200 K, covering the martian core conditions. The effects of hydrogen on the density and sound velocity of Fe-S liquids were investigated based on the calculated pressure-density-temperature data. Our results show that the calculated density of an Fe-S-H core can match that of the martian core, depending on the core sulfur and hydrogen contents and the seismic model used, but the corresponding sound velocity is always lower than the seismically observed P-wave velocity of the core. This implies that an additional light element, likely carbon, that can elevate the sound velocity of Fe-S liquids, must be present in the martian core.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143119914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}