China has carried out four unmanned missions to the Moon since it launched Chang’E-1,the first lunar orbiter in 2007.With the implementation of the Chang’E-5 mission this year,the three phases of the lunar explorati...China has carried out four unmanned missions to the Moon since it launched Chang’E-1,the first lunar orbiter in 2007.With the implementation of the Chang’E-5 mission this year,the three phases of the lunar exploration program,namely orbiting,landing and returning,have been completed.In the plan of follow-up unmanned lunar exploration missions,it is planned to establish an experimental lunar research station at the lunar south pole by 2030 through the implementation of several missions,laying a foundation for the establishment of practical lunar research station in the future.China successfully launched its first Mars probe on 23 July 2020,followed in future by an asteroid mission,second Mars mission,and a mission to explore Jupiter and its moons.展开更多
In recent years,the Lunar south pole region(SPR)has become the focus of future explorations due to its special illumination condition and the possible water ice in permanently shadowed craters around it.The Shackleton...In recent years,the Lunar south pole region(SPR)has become the focus of future explorations due to its special illumination condition and the possible water ice in permanently shadowed craters around it.The Shackleton crater locates almost exactly at the Moon’s south pole and has become the hottest destination for several landing missions,including the Chang’E-7 mission.However,people still know little about the electric potential and the dust environment around this crater.In this paper,we develop an analytical model to study the surface potential and the electrostatic dust transport around the crater.It is found that the crater’s floor can be negatively charged due to the topographic shielding,and the surface potential is as low as-175 V on the leeward crater wall.Accordingly,a large number of charged dust grains can be emitted from the leeward crater wall,with a maximum height of about 10 km and a horizontal distance of about 40 km,which brings a local dust cloud around the crater.Both the topographic shielding and the local dust cloud are qualitatively verified by a numerical simulation,in which a typical dust density of 10^(4)-10^(5)m^(-3)is found near the crater.Our results are important to the environmental assessment for future explorations near the crater.Furthermore,the results are helpful to understand the surface charging and the electrostatic dust transport on the other airless bodies.展开更多
针对月球南极光照暗弱、阴影区域众多、月面形貌要素单一弱纹理,给影像立体匹配和三维地形重建带来极大挑战和困难的问题,提出了一种可信度引导的高效立体匹配算法(Efficient Confidence-guided Stereo Matching,ECSM),通过评估非支撑...针对月球南极光照暗弱、阴影区域众多、月面形貌要素单一弱纹理,给影像立体匹配和三维地形重建带来极大挑战和困难的问题,提出了一种可信度引导的高效立体匹配算法(Efficient Confidence-guided Stereo Matching,ECSM),通过评估非支撑点的可信度来更新支撑点点集,构建三角网并利用三角形顶点的可信度重新估算其内部视差,提高匹配精度和效率。在此基础上,构建了月面摄影测量三维地形重建方法,并采用月球勘测轨道器(Lunar Reconnaissance Orbiter,LRO)窄角相机高分辨率影像数据,开展月球南极沙克尔顿(Shackleton)坑缘区域地形重建的验证实验。比较分析不同立体匹配算法生成的视差图和数字高程模型(Digital Elevation Model,DEM),结果表明:所提出的算法在处理月面弱纹理和重复纹理区域影像方面具有可靠性。将生成的DEM与德国宇航中心(Deutsches Zentrum für Luft-und Raumfahrt,DLR)制作的同区域DEM以及美国国家航空航天局(National Aeronautics and Space Administration,NASA)的月球轨道激光高度计DEM(LDEM)进行对比分析,高程和坡度信息方面都表现出较高的一致性,验证了该方法的可行性和有效性,为月球南极探测着陆区选择提供可靠的数据方法基础。展开更多
基金Supported by National Key R&D Program of China(2020YFE0202100)Beijing Municipal Science and Technology Commission(Z181100002918003)。
文摘China has carried out four unmanned missions to the Moon since it launched Chang’E-1,the first lunar orbiter in 2007.With the implementation of the Chang’E-5 mission this year,the three phases of the lunar exploration program,namely orbiting,landing and returning,have been completed.In the plan of follow-up unmanned lunar exploration missions,it is planned to establish an experimental lunar research station at the lunar south pole by 2030 through the implementation of several missions,laying a foundation for the establishment of practical lunar research station in the future.China successfully launched its first Mars probe on 23 July 2020,followed in future by an asteroid mission,second Mars mission,and a mission to explore Jupiter and its moons.
基金supported by the Youth Innovation Promotion Association of the Chinese Academy of Sciencessupported by the National Natural Science Foundation of China(Grant Nos.42174216,12075108,41903058&62371215)+2 种基金the Pre-research Project on Civil Aerospace Technologies by CNSA(Grant Nos.D050106,D020201)the Frontier Science Research Program of Deep Space Exploration Laboratory(Grant No.2022-QYKYJH-HXYF023)the Pandeng Program of National Space Science Center,Chinese Academy of Sciences。
文摘In recent years,the Lunar south pole region(SPR)has become the focus of future explorations due to its special illumination condition and the possible water ice in permanently shadowed craters around it.The Shackleton crater locates almost exactly at the Moon’s south pole and has become the hottest destination for several landing missions,including the Chang’E-7 mission.However,people still know little about the electric potential and the dust environment around this crater.In this paper,we develop an analytical model to study the surface potential and the electrostatic dust transport around the crater.It is found that the crater’s floor can be negatively charged due to the topographic shielding,and the surface potential is as low as-175 V on the leeward crater wall.Accordingly,a large number of charged dust grains can be emitted from the leeward crater wall,with a maximum height of about 10 km and a horizontal distance of about 40 km,which brings a local dust cloud around the crater.Both the topographic shielding and the local dust cloud are qualitatively verified by a numerical simulation,in which a typical dust density of 10^(4)-10^(5)m^(-3)is found near the crater.Our results are important to the environmental assessment for future explorations near the crater.Furthermore,the results are helpful to understand the surface charging and the electrostatic dust transport on the other airless bodies.
文摘针对月球南极光照暗弱、阴影区域众多、月面形貌要素单一弱纹理,给影像立体匹配和三维地形重建带来极大挑战和困难的问题,提出了一种可信度引导的高效立体匹配算法(Efficient Confidence-guided Stereo Matching,ECSM),通过评估非支撑点的可信度来更新支撑点点集,构建三角网并利用三角形顶点的可信度重新估算其内部视差,提高匹配精度和效率。在此基础上,构建了月面摄影测量三维地形重建方法,并采用月球勘测轨道器(Lunar Reconnaissance Orbiter,LRO)窄角相机高分辨率影像数据,开展月球南极沙克尔顿(Shackleton)坑缘区域地形重建的验证实验。比较分析不同立体匹配算法生成的视差图和数字高程模型(Digital Elevation Model,DEM),结果表明:所提出的算法在处理月面弱纹理和重复纹理区域影像方面具有可靠性。将生成的DEM与德国宇航中心(Deutsches Zentrum für Luft-und Raumfahrt,DLR)制作的同区域DEM以及美国国家航空航天局(National Aeronautics and Space Administration,NASA)的月球轨道激光高度计DEM(LDEM)进行对比分析,高程和坡度信息方面都表现出较高的一致性,验证了该方法的可行性和有效性,为月球南极探测着陆区选择提供可靠的数据方法基础。
