Journal of Geophysical Research: Planets最新文献

{"title":"The Coprecipitation of Akaganeite and Jarosite and Its Implications for the Late-Stage Diagenetic Fluids in the Vera Rubin Ridge, Gale Crater, Mars","authors":"Lingxi Zhang,&nbsp;Xiaohui Fu,&nbsp;Zongcheng Ling,&nbsp;Erbin Shi,&nbsp;Haijun Cao","doi":"10.1029/2023JE008157","DOIUrl":"https://doi.org/10.1029/2023JE008157","url":null,"abstract":"<p>Akaganeite and jarosite were detected in two mudstone drill samples from Vera Rubin ridge (VRR), Gale crater by Chemistry &amp; Mineralogy X-Ray Diffraction (CheMin). The co-occurrence of these two minerals is quite rare in both terrestrial and Martian aqueous environments. In order to confine the chemical conditions of paragenetic akaganeite and jarosite, and provide insight into late-stage diagenetic alterations at VRR, we synthesized akaganeite and jarosite with varying SO₄²⁻ concentrations and initial pH levels. Synthetic samples were characterized using Field Emission Scanning Electron Microscopy, X-ray powder diffraction and Raman spectroscopy. Our study reveals that akaganeite and jarosite exist in equilibrium in the solution with 0.011–0.028 M SO₄²⁻ with respect to 0.6 M Cl⁻ and an initial pH of 1.3–2.2. In combination with the CheMin detection results, the chemistry and pH values of the fluids at VRR can be further constrained. Considering the absence of goethite and the relative higher portion of akaganeite than jarosite in the drill samples, the pH values should be 1.4–2 and the S/Cl molar ratio should be within the range of 0.018–0.042. Based on our laboratory results, we hypothesize that the presence of akaganeite and jarosite at VRR represents an individual episode of acidic groundwater activity. During the late-stage diagenetic process at VRR, upwelled acidic groundwater dissolved the local chlorides to form the Cl⁻-dominated fluids. Subsequent evaporation further concentrated the acid saline fluids and therefore resulted in an extremely acidic environment (1.4 ≤ pH＜2 with S/Cl molar ratio of 0.018–0.042), which produced akaganeite and jarosite.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140621312","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":"Thermoelastic Properties and Thermal Evolution of the Martian Core From Ab Initio Calculated Magnetic Fe-S Liquid","authors":"Wei-Jie Li,&nbsp;Zi Li,&nbsp;Zhe Ma,&nbsp;Jie Zhou,&nbsp;Cong Wang,&nbsp;Ping Zhang","doi":"10.1029/2023JE007874","DOIUrl":"https://doi.org/10.1029/2023JE007874","url":null,"abstract":"<p>Accurate thermoelastic properties and thermal conductivity are crucial for understanding the thermal evolution of the Martian core. A fitting method based on ab initio calculated pressure-volume-temperature data was proposed for the formulation of the equation of state with high accuracy, by which the pressure and temperature dependent thermoelastic properties can be directly calculated by definitions. Ab initio results showed that Fe_0.75S_0.25 liquid under Martian core conditions was thoroughly in a magnetic state without existing spin crossover. The Fe_0.75S_0.25 liquid in magnetic calculations had a low thermal conductivity (21–23 W/m/K) when compared with non-magnetic calculations at the same state. Based on Insight's estimated Martian core properties (Stähler et al., 2021, https://doi.org/10.1126/science.abi7730) and ab initio calculated properties of the Fe_0.75S_0.25 liquid, the scenario for the thermal evolution of the Martian core is the iron-snow model crystallization regime. The parameter uncertainty effect on the cessation time of the dynamo and zone of iron snow was systematically analyzed.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140621313","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":"Retrieval of Ar, N2, O, and CO in the Martian Thermosphere Using Dayglow Limb Observations by EMM EMUS","authors":"J. S. Evans,&nbsp;J. Deighan,&nbsp;S. Jain,&nbsp;V. Veibell,&nbsp;J. Correira,&nbsp;H. Al Matroushi,&nbsp;H. Al Mazmi,&nbsp;M. Chaffin,&nbsp;S. Curry,&nbsp;N. El-Kork,&nbsp;S. England,&nbsp;F. Eparvier,&nbsp;M. Fillingim,&nbsp;G. Holsclaw,&nbsp;M. Khalil,&nbsp;R. Lillis,&nbsp;F. Lootah,&nbsp;S. Mahmoud,&nbsp;T. Plummer,&nbsp;E. Soto,&nbsp;J. Tennyson,&nbsp;E. Thiemann,&nbsp;S. N. Yurchenko","doi":"10.1029/2023JE008181","DOIUrl":"https://doi.org/10.1029/2023JE008181","url":null,"abstract":"<p>The Emirates Ultraviolet Spectrometer (EMUS) onboard the Emirates Mars Mission (EMM) Hope probe images Mars at wavelengths extending from approximately 100 to 170 nm. EMUS observations began in February 2021 and cover over a full Mars year. We report the first limb scan observations at Mars of ultraviolet emissions Ar I 106.6 nm, N I 120 nm, and carbon monoxide (CO) Fourth Positive Group (<i>A</i> − <i>X</i>) band system excited by electron impact on CO. We use EMUS limb scan observations to retrieve number density profiles of argon, molecular nitrogen, atomic oxygen, and CO in the upper atmosphere of Mars from 130 to 160 km. CO is a sensitive tracer of the thermal profile and winds in Mars' middle atmosphere and the chemistry that balances CO₂ in the atmosphere of Mars. EMUS insertion orbit special observations demonstrate that far ultraviolet limb measurements of the Martian thermosphere can be spectroscopically analyzed with a robust retrieval algorithm to further quantify variations of CO composition in the Martian upper atmosphere.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023JE008181","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140621314","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":"Using Io's Sulfur Isotope Cycle to Understand the History of Tidal Heating","authors":"Ery C. Hughes,&nbsp;Katherine de Kleer,&nbsp;John Eiler,&nbsp;Francis Nimmo,&nbsp;Kathleen Mandt,&nbsp;Amy E. Hofmann","doi":"10.1029/2023JE008086","DOIUrl":"https://doi.org/10.1029/2023JE008086","url":null,"abstract":"<p>Stable isotope fractionation of sulfur offers a window into Io's tidal heating history, which is difficult to constrain because Io's dynamic atmosphere and high resurfacing rates leave it with a young surface. We constructed a numerical model to describe the fluxes in Io's sulfur cycle using literature constraints on rates and isotopic fractionations of relevant processes. Combining our numerical model with measurements of the ³⁴S/³²S ratio in Io's atmosphere, we constrain the rates for the processes that move sulfur between reservoirs and model the evolution of sulfur isotopes over time. Gravitational stratification of SO₂ in the upper atmosphere, leading to a decrease in ³⁴S/³²S with increasing altitude, is the main cause of sulfur isotopic fractionation associated with loss to space. Efficient recycling of the atmospheric escape residue into the interior is required to explain the ³⁴S/³²S enrichment magnitude measured in the modern atmosphere. We hypothesize this recycling occurs by SO₂ surface frost burial and SO₂ reaction with crustal rocks, which founder into the mantle and/or mix with mantle-derived magmas as they ascend. Therefore, we predict that magmatic SO₂ plumes vented from the mantle to the atmosphere will have lower ³⁴S/³²S than the ambient atmosphere, yet are still significantly enriched compared to solar-system average sulfur. Observations of atmospheric variations in ³⁴S/³²S with time and/or location could reveal the average mantle melting rate and hence whether the current tidal heating rate is anomalous compared to Io's long-term average. Our modeling suggests that tides have heated Io for &gt;1.6 Gyr if Io today is representative of past Io.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023JE008086","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140606288","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":"Atmospheric Tides in the Middle and Upper Atmosphere of Mars at Northern High Latitudes: A Comparison of MAVEN-EUVM and MRO-MCS Observations With Model Results","authors":"Aishwarya Kumar,&nbsp;Scott L. England,&nbsp;Guiping Liu,&nbsp;Edward M. B. Thiemann","doi":"10.1029/2023JE007887","DOIUrl":"https://doi.org/10.1029/2023JE007887","url":null,"abstract":"<p>Much of the variability in the Martian thermosphere can be attributed to vertically propagating atmospheric tides that are known to achieve significant amplitudes in this region. Concurrent observations from different altitudes have been used previously to discern the vertical propagation characteristics of tides but have primarily focused on low latitudes. The spectrum of tides and their vertical evolution are thereby less constrained at high latitudes. Few studies that have focused on high latitudes identified wavenumber-3 structures which were interpreted to originate mainly from the non-migrating tides SE1 and DE2. This paper presents the first analysis of MAVEN-EUVM solar occultation observations to deduce atmospheric tides in the Martian thermosphere. These are compared to tides observed by MRO-MCS in the middle atmosphere for six cases at high northern latitudes. To identify vertical propagation, wave signatures in the middle and upper atmosphere are compared and are found to be dominated by a mix of zonal wavenumbers-2 and -3 in fixed local time. MCS observations show eastward propagating tides dominate, specifically highlighting SE1 near 76 km. Additionally, these observations indicate the presence of stationary planetary waves and terdiurnal tides. Mars Climate Database also indicates the presence of SE1, DE2, DE1, S0, TW1, and T0 tides. A change in the dominant wavenumber component with local time is seen, which is attributed to the presence of all three diurnal, semidiurnal and terdiurnal components at these latitudes. The significant decrease in the diurnal tide amplitude indicates the effect of zonal mean wind on vertical propagation.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023JE007887","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140606262","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":"Mineralogical Characterization of the Lunar South Polar Region: 1. The Artemis Exploration Zone","authors":"D. P. Moriarty III,&nbsp;N. E. Petro","doi":"10.1029/2023JE008266","DOIUrl":"https://doi.org/10.1029/2023JE008266","url":null,"abstract":"<p>The lunar south pole is a region of focused scientific and exploration interest, with several crewed and robotic missions to this region planned within the next decade. Understanding the mineralogy of the region is essential to inform landing site characterization and selection and provides the key context for interpreting samples and in situ observations. At high latitudes, extreme illumination conditions (high phase angles) can negatively impact the data quality of orbital instruments. This is especially true for passive near-infrared spectrometers such as the Moon Mineralogy Mapper (M³) and the Kaguya Spectral Profiler, which measure the spectral properties of the surface using reflected sunlight. Using Moon Mineralogy Mapper data, we observed that the south polar region is associated with a detectable mafic signature consistent with the presence of pyroxenes. The strongest mafic signatures are associated with the South Pole—Aitken Basin, suggesting that impact melt and basin ejecta from the lower crust and upper mantle are present within this region. This observation is validated in several ways: (a) comparisons between M³ data acquired during different mission phases, (b) comparisons between multiple spectral parameters sensitive to the presence of mafic minerals, (c) comparisons between the north and south lunar polar regions, and (d) comparisons with publicly available Kaguya polar mineralogy maps and Lunar Prospector elemental abundances. We also investigate the nature of an anomalous high-albedo region within 2–3° of the south pole observed in Lunar Orbiter Laser Altimeter reflectance data exhibiting a spatially conflicting apparent FeO abundance pattern between several data sets.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023JE008266","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140606382","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":"Iron-Rich Grain-Decorated Depressions on Surfaces of Lunar Impact Glasses","authors":"Pan Yan,&nbsp;Zhiyong Xiao,&nbsp;Yanxue Wu,&nbsp;Qing Pan,&nbsp;Yunhua Wu","doi":"10.1029/2024JE008284","DOIUrl":"https://doi.org/10.1029/2024JE008284","url":null,"abstract":"<p>Iron-rich particles are widespread on the surfaces and interiors of lunar impact glasses, and they record delicate physicochemical processes during space weathering and regolith gardening on the Moon. Different from nanophase iron in amorphous rims of regolith minerals, iron-rich particles in lunar impact glasses are mostly larger than 10 nm and are spherical and semi-hemispherical in shape. In regolith samples returned by Luna, Apollo and Chang'E-5 missions, a special form of microscopic iron-rich structure commonly exists on surfaces of impact glasses, which appear as rimless depressions that are filled with nano-sized grains. Termed grain-decorated iron-rich depressions, their possible origin is elusive. Here we perform detailed observations of the morphology, composition and crystallography of these microstructures, showing that they are not degassing pits that were later filled with nano-sized grains as has been previously considered. They are hemispherical integrated compounds of α-Fe and troilite that have variable area proportion. The surface grains are dominated by α-Fe, which mainly develop on top of vesiculated surfaces of the underlying troilite. The α-Fe grains are mainly formed by desulphurization of troilite due to radiation and heating. While iron-rich grain-decorated depressions have larger diameters and different surface morphologies compared to other iron-rich microstructures in lunar impact glasses, their identical occurrences and phase components (α-Fe and troilite) suggest a common origin caused by liquid immiscibility between Fe-S melt and silicate melt. Their diverse surface morphology is mainly caused by heterogeneous S contents and local ratios of Fe and S in silicate impact melt.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140606486","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":"Climatology and Diurnal Variation of Ozone Column Abundances for 2.5 Mars Years as Measured by the NOMAD-UVIS Spectrometer","authors":"J. P. Mason,&nbsp;M. R. Patel,&nbsp;J. A. Holmes,&nbsp;M. J. Wolff,&nbsp;J. Alday,&nbsp;P. Streeter,&nbsp;K. S. Olsen,&nbsp;M. A. J. Brown,&nbsp;G. Sellers,&nbsp;C. Marriner,&nbsp;Y. Willame,&nbsp;I. Thomas,&nbsp;B. Ristic,&nbsp;F. Daerden,&nbsp;A. C. Vandaele,&nbsp;J.-J. Lopez-Moreno,&nbsp;G. Bellucci","doi":"10.1029/2023JE008270","DOIUrl":"https://doi.org/10.1029/2023JE008270","url":null,"abstract":"<p>The distribution of Mars ozone (O₃) is well established; however, our knowledge on the dayside diurnal variation of O₃ is limited. We present measurements of Mars O₃ column abundances, spanning Mars Year (MY) 34 to the end of MY 36, by the Ultraviolet and VIsible Spectrometer (UVIS), part of the Nadir and Occultation for MArs Discovery (NOMAD) instrument, aboard the ExoMars Trace Gas Orbiter. UVIS provides the capability to measure dayside diurnal variations of O₃ and for the first time, a characterization of the dayside diurnal variations of O₃ is attempted. The observed O₃ climatology for Mars Years (MY) 34–36 follows the established seasonal trends observed through previous O₃ measurements. At aphelion, the equatorial O₃ distribution is observed to be strongly correlated with the water ice distribution. We show that the early dust storm in MY 35 resulted in a near-global reduction in O₃ during northern spring and the O₃ abundances remained 14% lower in northern summer compared to MY36. Strong latitudinal and longitudinal variation was observed in the diurnal behavior of O₃ around the northern summer solstice. In areas with a weak O₃ upper layer, O₃ column abundance peaks in the mid-morning, driven by changes in the near-surface O₃ layer. In regions with greater O₃ column abundances, O₃ is observed to gradually increase throughout the day. This is consistent with the expected diurnal trend of O₃ above the hygropause and suggests that in these areas an upper O₃ layer persists throughout the Martian day.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023JE008270","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140606226","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":"On the Global Features of the 10–60-Min ULF Waves in Jovian Magnetosphere: Juno Observations","authors":"J. W. Sun,&nbsp;L. Xie,&nbsp;Z. H. Yao,&nbsp;S. Y. Fu,&nbsp;W. R. Dunn,&nbsp;D. Grodent,&nbsp;B. Bonfond,&nbsp;B. Zhang,&nbsp;D. X. Pan,&nbsp;Y. Xu,&nbsp;Y. N. Chen","doi":"10.1029/2023JE008279","DOIUrl":"https://doi.org/10.1029/2023JE008279","url":null,"abstract":"<p>In the Jovian magnetosphere, quasi-periodic phenomena, with quasi-periods on the order of 10–60 min, are frequently identified using different data sets. These pulsations are a branch of ultra-low frequency (ULF) waves, which are believed to play a crucial role in driving the energy circulation within Jupiter's magnetosphere. In this study, we utilize magnetic field data collected by Juno between 2016 and 2022 to perform a comprehensive global statistical analysis of the spatial distribution and periodic characteristics of ULF waves in the Jovian magnetosphere. Our findings reveal distinct periodic features observed at different latitudes and distances, providing valuable insights into the generation mechanisms of ULF waves. Furthermore, we establish a close relationship between the presence of these ULF wave fluctuations and the magnetospheric state, such as under conditions of solar wind compression. By combining contemporaneous ultraviolet aurora observations from the Hubble Space Telescope (HST) and magnetic field data obtained by Juno, we have discovered that the compressed magnetospheres exhibit more pronounced ULF waves and enhanced auroral activity. These results provide a global picture of the distribution, implying potential generation of ULF waves in the Jovian magnetosphere, and shedding light on the processes behind the 10–60-min energy releases.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140556267","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":"Soluble Organic Compounds and Cyanide in Apollo 17 Lunar Samples: Origins and Curation Effects","authors":"Jamie E. Elsila,&nbsp;José C. Aponte,&nbsp;Hannah L. McLain,&nbsp;Danielle N. Simkus,&nbsp;Jason P. Dworkin,&nbsp;Daniel P. Glavin,&nbsp;Ryan A. Zeigler,&nbsp;Francis M. McCubbin,&nbsp;the ANGSA Science Team","doi":"10.1029/2023JE008133","DOIUrl":"https://doi.org/10.1029/2023JE008133","url":null,"abstract":"<p>We analyzed 12 Apollo 17 samples through the Apollo Next Generation Sample Analysis (ANGSA) program to determine the abundances of a variety of compound classes, including amino acids, aldehydes, ketones, amines, carboxylic acids, and cyanide-releasing species. Analyzed samples included portions of double drive tube 73001/73002, the bottom half of which (73001) was hermetically sealed under lunar vacuum, as well as lunar regolith samples from three different illumination environments that had been curated frozen for ∼50 years. Consistent with previous results, we detected low levels of amino acids in the hot-water extracts of most samples (0.55–12.03 nmol/g in unhydrolyzed samples; 0.53–72.38 nmol/g after acid hydrolysis of the extracts). We also detected one-carbon and two-carbon species of amines, aldehydes, and carboxylic acids (i.e., methylamine, ethylamine, formaldehyde, acetaldehyde, formic acid, acetic acid) not previously reported in lunar samples, as well as insoluble cyanide-forming species. Although these compounds are potential precursor molecules for amino acids, no specific precursor relationships could be determined. Nylon contamination was the likely source of some amino acids. Abundances of some species (e.g., cyanide) decreased with increasing depth in the drive tube, suggesting that exogenous delivery and concentration mechanisms near the surface outweighed surface degradation processes. In addition, we observed the potential cold trapping of volatile amines in the persistently shadowed samples analyzed. Finally, we noted the effects of different curation conditions; hermetic sealing appeared to preserve higher amounts of volatile compounds, while frozen curation did not have a noticeable preservation effect on the organic volatiles analyzed here.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140556138","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}