用LLR资料解算日月轨道根数     

白金明  金文敬 《天文学报》1994,35(4):424-433

本文推导了激光测月资料归算中测距对地月系轨道根数的偏导数，并对所得偏导数进行了精度估计，利用这些偏导数和１９８８年至１９９２年全球激光测月资料解算了日月轨道根数，得到了比较理想的结果。  相似文献   

Rapid screening of Zr-containing particles from Chang’e-5 lunar soil samples for isotope geochronology: Technical roadmap for future study     

《地学前缘(英文版)》2022,13(3):101367

New samples returned by China Chang’e-5 (CE-5) mission offer an opportunity for studying the lunar geologic longevity, space weathering, and regolith evolution. The age determination of the CE-5 samples was among the first scientific questions to be answered. However, the precious samples, most in the micrometer size range, challenge many traditional analyses on large single crystals of zircon developed for massive bulk samples. Here, we developed a non-destructive rapid screening of individual zirconium-containing particle for isotope geochronology based on a Micro X-ray fluorescence analysis (µXRF). The selected particles were verified via scanning electron microscopy (SEM), 3D X-ray microscopy (XRM), and focused ion beam scanning electron microscopy (FIB-SEM) techniques, which showed that zirconium-bearing minerals with several microns were precisely positioned and readily suitable for site-specific isotopic dating by second ion mass spectrometry (SIMS). Such protocol could be also applicable in non-destructively screening other types of particles for different scientific purposes. We therefore proposed a correlative workflow for comprehensively studying the CE-5 lunar samples from single particles on nanometer to atomic scales. Linking various microscopic and spectromicroscopic instruments together, this workflow consists of six steps: (1) single-particle selection with non-destructive µXRF technique, (2) 2D/3D morphological and structural characterization with a correlative submicron 3D XRM and nanoscale resolution FIB-SEM imaging methods, (3) SEM analysis of the surface morphology and chemistry of the selected particle, (4) a series of microscopic and microbeam analyses (e.g., SEM, electron probe microanalysis, and SIMS) on the cross-section of the selected particle to obtain structural, mineralogical, chemical, and isotopic features from the micron to nanometer scale, (5) advanced 2D/3D characterization and site-specific sample preparation of thin foil/tip specimens on a microregion of interest in the selected particle with FIB-SEM technique, and (6) comprehensive analyses on the FIB-milled specimens at nanometer to atomic scale with synchrotron-based scanning transmission X-ray microscopy, analytic transmission electron microscopy, and atom probe tomography. Following this technical roadmap, one can integrate multiple modalities into a uniform frame of multimodal and multiscale correlated datasets to acquire high-throughput information on the limited or precious terrestrial and extraterrestrial samples.  相似文献   

热力学计算模拟对初始月幔结构的约束SCIEI北大核心CSCD     

鞠东阳  庞润连  李瑞  杜蔚 《岩石学报》2022,38(4):1025-1042

月球岩浆洋结晶形成的初始月球内部结构是其后续演化过程的开端,其结晶过程受月球岩浆洋的初始深度和物质组成这两个参数的制约。由于缺少直接来自月球深部的岩石样品,目前关于月球岩浆洋演化过程的探讨主要依赖实验和计算模拟手段。岩浆洋模型中形成的月壳厚度是否与探测结果一致是月球岩浆洋演化模型合理性的重要约束。最新的GRAIL(Gravity Recovery and Interior Laboratory)探测数据推算月壳厚度为34~43km,低于阿波罗时期认为的约70km,这对已有的月球岩浆洋演化模型提出了挑战。本文采用并修正FXMOTR程序包,针对月球岩浆洋在不同的初始深度和物质组成情况下的结晶过程,进行了一系列热力学计算模拟。通过量化月球岩浆洋的初始深度和物质组成对月壳厚度的影响,结合关于月球内部微量元素分配的研究结果,对比了月球岩浆洋结晶后期的残余熔体与原始克里普组分(urKREEP)的成分。本文的模拟结果显示,一个全月幔熔融且初始成分为月球初始上月幔组成(LPUM)的岩浆洋将在其深部结晶2.5%石榴子石,形成的月壳厚度符合GRAIL的约束,并且结晶出了合适的urKREEP成分。在此模型的基础上获取了月球初始的内部成分和密度结构,并对后期月幔翻转(Overturn)的程度进行了探讨。  相似文献   

Research in Astronomy and Astrophysics CONTENTS     

《中国天文和天体物理学报》2014,(12)

正~~  相似文献   

铜陵凤凰山铜矿区角砾岩特征及其成因分析   总被引：3，自引：0，他引：3  

毛政利  杨斌  赖健清 《矿物岩石》2004,24(1):29-32

凤凰山铜矿区矿体附近不同类型角砾岩的分形统计分析结果表明,其中角砾状花岗闪长岩的形成以化学作用为主,其颗粒大小分布的分维值达到了1．389,说明其在形成过程中经历了机械破裂过程,其破裂过程中的能量达到中等。角砾状矿石和角砾状大理岩均为水力致裂角砾岩,角砾状矿石的颗粒大小分布的分维值(1．526)大于角砾状大理岩(1．24),指示了角砾状矿石形成时的能量大于角砾状大理岩。  相似文献   

Non-Continuation of Integrals of the Rotating Two-body Problem in Hill's Lunar Problem     

Fabian Josef Winterberg  Efi Meletlidou 《Celestial Mechanics and Dynamical Astronomy》2004,88(1):37-49

We consider Hill's lunar problem as a perturbation of the integrable two-body problem. For this we avoid the usual normalization in which the angular velocity of the rotating frame of reference is put equal to unity and consider as the perturbation parameter. We first express the Hamiltonian H of Hill's lunar problem in the Delaunay variables. More precisely we deduce the expressions of H along the orbits of the two-body problem. Afterwards with the help of the conserved quantities of the planar two-body problem (energy, angular momentum and Laplace–Runge–Lenz vector) we prove that Hill's lunar problem does not possess a second integral of motion, independent of H, in the sense that there exist no analytic continuation of integrals, which are linear functions of in the rotating two-body problem. In connection with the proof of this main result we give a further restrictive statement to the nonintegrability of Hill's lunar problem.  相似文献   

一种基于嫦娥一号CCD影像的影像匹配方法     

何钰  蓝朝桢  邢帅 《测绘科学技术学报》2012,(4):281-284

月球测绘是完成月球探测任务的基础保障。这里提出了一种适合于CE-1获取的CCD影像的多尺度约束自动匹配方法。首先利用SURF算子提取影像上特征点;然后进行基于准核线和最小欧式距离约束的影像匹配;最后采用随机采样算法对误匹配点进行剔除而得到同名点信息。实验结果表明,该匹配方法提取的同名点有利于CE-1月球影像DEM的生成。  相似文献   

月球Airy均衡状态与月壳厚度估计   总被引：2，自引：0，他引：2  

丰海  李建成  李大炜  张守建  刘志勇 《测绘学报》2012,41(4):543-548

月球水准面异常和表面地形变化是其内部密度不均匀和各个界面的起伏变化的体现,因此利用水准面和地形之比(geoid to topography ratio,GTR)可估计月球均衡和月壳厚度。本文基于月球重力场模型SGM100h和地形模型STM359_grid-02,经过去除表面玄武岩填充和深层异常质量影响,并结合理论Airy均衡模型中GTR与参考月壳厚度的关系,计算得到了新的月壳厚度模型。该模型的月壳平均厚度为36.9 km,背面比正面平均厚约13.5 km,Apollo12/14登陆点的月壳厚度分别是28.3 km和29.1 km。在各月海盆地存在着中央较薄、四周逐渐增厚的趋势。  相似文献   

月球资源探测信息的管理与可视化探讨   总被引：1，自引：0，他引：1  

吴冲龙  毛小平  田宜平  张夏林  翁正平 《地质科技情报》2004,23(4):15-18

在中国未来的月球探测计划中,可能获取的月球表层数据包括地形、地貌、岩层、土壤、资源、环境以及各种相关的结构、物质成分数据。这些数据既有空间数据,也有属性数据。为了实现月球资源探测工作信息化,可以借鉴“数字地球”的理念并采用“多S”结合与集成化技术,对所获取的海量月球表层数据进行一体化存贮管理,构建一个“数字月球”并实现其空间数据和属性数据之间的双向查询检索,以及对表层复杂结构信息分析的可视化。  相似文献   

苏州西山震裂锥:太湖冲击坑又一新证据          下载免费PDF全文

王鹤年  钱汉东  陈旸  周丽娅 《高校地质学报》2019,25(1):58

震裂锥已被公认为陨石冲击地球表面遗留的标志。研究及统计资料表明,震裂锥与陨石冲击形成的中、大型冲击坑 有关。太湖西山震裂锥呈圆锥形,锥体表面有自锥顶向下辐射的锥纹,锥纹具有分叉的特征,这些特征与震裂锥的国际公 认的定义和标准相符。此外,西山震裂锥还具有其特有的其他特征：碎裂岩化显著;气化-熔融现象发育;锥体表面具网 状构造及波纹状、蜂窝状等多种气印。岩相学研究显示,震裂锥及含锥岩石中冲击变质现象明显,微页理（PDFs）、微裂 隙（PFs） 以及靶岩熔融现象发育。以上这些冲击变质的标志,可证明西山震裂锥是冲击成因,而非地表水风化淋溶石灰岩 的喀斯特或风蚀成因的凤稜石。西山震裂锥的发现、太湖湖底冲击击变角砾岩“太湖石”的确定,为太湖冲击坑的研究增 添了新的诊断性证据;加上早期研究确定的、冲击回落至太湖湖底淤泥层中的冲击溅射物,这些众多证据为确定“太湖冲 击坑”或“太湖冲击事件”展示了美好前景。但是,要确定太湖冲击坑的具体位置、大小及构造模式等,尚需更多的深入 研究。  相似文献