The Martian core mainly contains iron,nickel and some light elements.However,controversies remain about the structure and chemical composition of the Martian core due to a lack of samples and marsquake data.Recently,t...The Martian core mainly contains iron,nickel and some light elements.However,controversies remain about the structure and chemical composition of the Martian core due to a lack of samples and marsquake data.Recently,the InSight lander collected long-term marsquake data,which improved the Martian interior structure model.B ased on the preliminary analysis of marsquake data,Mars has a molten liquid core with a radius of around 1700 km.As the Martian core has a smaller density and lower temperature than pure iron at corresponding pressure and temperature conditions,some light elements are introduced to reduce the density and liquidus temperature.With various methods for seismic analysis,in-situ high-pressure and high-temperature experiments,and first-principal calculations,the Martian core composition and evolution models have been updated in the past few years.Here,we review those studies on the light elements in the Martian core from four aspects including(1)high-temperature and high-pressure experiments,(2)marsquake data,(3)mineral physics model with molecular dynamics simulations and(4)cosmochemistry investigation.We discussed the effect of different light elements on the Martian core s density,sound velocity and liquidus temperature.Moreover,the review examines the varieties,abundances and forms of light elements in the Martian core.展开更多
Understanding the interaction of Martian rocks and the environment is conducive to Mars in situ resource utilization(ISRU) and the search for natural H_(2) reservoirs. Here, we report an interesting finding: using a r...Understanding the interaction of Martian rocks and the environment is conducive to Mars in situ resource utilization(ISRU) and the search for natural H_(2) reservoirs. Here, we report an interesting finding: using a real Martian meteorite(NWA13190) and within Mars' temperature range(25℃), we confirmed spontaneous hydrogen generation from the reaction of water, CO_(2), and Martian rock—no external energy or catalysts required. The reaction produced hydrogen at ~4 ppm/day, stabilizing after 9 days, alongside newly formed carbonate and sulfate minerals absent in the original meteorite. Mechanistic analyses using XPS(X-ray photoelectron spectroscopy), M??ssbauer spectroscopy, and FTIR(Fourier transform infrared spectroscopy) revealed that Fe^(2+) in Fe TiO_(3) and FeS_(2)(not pyroxene) oxidized to Fe^(3+), driving water reduction to hydrogen. The buffer effect of CO_(2) sustained acidic conditions, enhancing Fe^(2+) release and H_(2) production. These results align with in situ Mars detections(e.g., Ca-sulfate veins by Curiosity). Compared with energy-intensive electrolysis-based ISRU, this geological process offers a more efficient H_(2) production pathway. It also provides theoretical support for natural hydrogen reservoirs on Mars and simultaneously advances understanding of Mars' early atmospheric evolution and potential life-supporting environments.展开更多
类火星地貌识别分类旨在通过分析类火星地貌图像,模拟研究火星环境,对火星形成演化及潜在宜居环境探索等科学问题具有重要研究意义。针对目前火星地貌分类算法难以平衡模型分类效果和轻量化程度的问题,提出一种轻量化类火星地貌快速识...类火星地貌识别分类旨在通过分析类火星地貌图像,模拟研究火星环境,对火星形成演化及潜在宜居环境探索等科学问题具有重要研究意义。针对目前火星地貌分类算法难以平衡模型分类效果和轻量化程度的问题,提出一种轻量化类火星地貌快速识别分类方法(Lightweight Rapid Recognition and Classification for Mars Analog Terrain,LWNet),构建双分支教师-学生网络,利用知识蒸馏技术减少模型参数量与计算量,并嵌入注意力机制提高对地貌类型的分类识别能力,实现分类模型的高精度和轻量化。为验证所提方法的分类性能表现,通过采集地球上相似地貌,构建了包括悬崖断面、沙漠、河道及雅丹在内的4种典型类火星地貌数据集,每种地貌类型各获取800张图像,用于LWNet开展快速识别分类实验。结果表明,LWNet总体分类精度达到97.81%,相较于精度最高的Swin-Transformer仅下降了1.25%,而其参数量和计算量却只有Swin-Transformer的1.3%和4.8%,验证了所提轻量化类火星地貌快速识别分类方法的有效性和优越性。展开更多
基金financially supported by the National Natural Science Foundation of China(grant no.42120104005)Guizhou Provincial 2021 Science and Technology Subsidies(grant no.GZ2021SIG)+1 种基金Guizhou Provincial Science and Technology Projects(grant nos.ZK[2024]087GCC[2023]060)。
文摘The Martian core mainly contains iron,nickel and some light elements.However,controversies remain about the structure and chemical composition of the Martian core due to a lack of samples and marsquake data.Recently,the InSight lander collected long-term marsquake data,which improved the Martian interior structure model.B ased on the preliminary analysis of marsquake data,Mars has a molten liquid core with a radius of around 1700 km.As the Martian core has a smaller density and lower temperature than pure iron at corresponding pressure and temperature conditions,some light elements are introduced to reduce the density and liquidus temperature.With various methods for seismic analysis,in-situ high-pressure and high-temperature experiments,and first-principal calculations,the Martian core composition and evolution models have been updated in the past few years.Here,we review those studies on the light elements in the Martian core from four aspects including(1)high-temperature and high-pressure experiments,(2)marsquake data,(3)mineral physics model with molecular dynamics simulations and(4)cosmochemistry investigation.We discussed the effect of different light elements on the Martian core s density,sound velocity and liquidus temperature.Moreover,the review examines the varieties,abundances and forms of light elements in the Martian core.
基金supported by the National Natural Science Foundation of China (Grant Nos.41807188,42402285,51978537,52270165)the Fundamental Research Funds for the Central Universities (Grant No.2042021kf0201)Start-up Fund for Distinguished Scholars,Wuhan University (Grant Nos.1403-413100041,1403-600460022)。
文摘Understanding the interaction of Martian rocks and the environment is conducive to Mars in situ resource utilization(ISRU) and the search for natural H_(2) reservoirs. Here, we report an interesting finding: using a real Martian meteorite(NWA13190) and within Mars' temperature range(25℃), we confirmed spontaneous hydrogen generation from the reaction of water, CO_(2), and Martian rock—no external energy or catalysts required. The reaction produced hydrogen at ~4 ppm/day, stabilizing after 9 days, alongside newly formed carbonate and sulfate minerals absent in the original meteorite. Mechanistic analyses using XPS(X-ray photoelectron spectroscopy), M??ssbauer spectroscopy, and FTIR(Fourier transform infrared spectroscopy) revealed that Fe^(2+) in Fe TiO_(3) and FeS_(2)(not pyroxene) oxidized to Fe^(3+), driving water reduction to hydrogen. The buffer effect of CO_(2) sustained acidic conditions, enhancing Fe^(2+) release and H_(2) production. These results align with in situ Mars detections(e.g., Ca-sulfate veins by Curiosity). Compared with energy-intensive electrolysis-based ISRU, this geological process offers a more efficient H_(2) production pathway. It also provides theoretical support for natural hydrogen reservoirs on Mars and simultaneously advances understanding of Mars' early atmospheric evolution and potential life-supporting environments.
文摘类火星地貌识别分类旨在通过分析类火星地貌图像,模拟研究火星环境,对火星形成演化及潜在宜居环境探索等科学问题具有重要研究意义。针对目前火星地貌分类算法难以平衡模型分类效果和轻量化程度的问题,提出一种轻量化类火星地貌快速识别分类方法(Lightweight Rapid Recognition and Classification for Mars Analog Terrain,LWNet),构建双分支教师-学生网络,利用知识蒸馏技术减少模型参数量与计算量,并嵌入注意力机制提高对地貌类型的分类识别能力,实现分类模型的高精度和轻量化。为验证所提方法的分类性能表现,通过采集地球上相似地貌,构建了包括悬崖断面、沙漠、河道及雅丹在内的4种典型类火星地貌数据集,每种地貌类型各获取800张图像,用于LWNet开展快速识别分类实验。结果表明,LWNet总体分类精度达到97.81%,相较于精度最高的Swin-Transformer仅下降了1.25%,而其参数量和计算量却只有Swin-Transformer的1.3%和4.8%,验证了所提轻量化类火星地貌快速识别分类方法的有效性和优越性。
