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61.
深部月壳和月幔物质结构是月球科学探测的关键问题之一。“嫦娥4号”初步将月球背面南极—艾肯(South Pole-Aitken,SPA)盆地内的冯·卡门(Von Kármán)撞击坑作为着陆点,具有重要的科学研究价值。结合月球重力、地形、布格重力、月壳厚度等地球物理数据,综合对冯·卡门撞击坑的月壳及其深部结构特征进行了分析。结果显示:冯·卡门撞击坑重复撞击到南部的冯·卡门M撞击坑上,后者的中央峰具有明显的布格正重力异常和线性的布格重力梯度特征,显示出高密度的幔部物质向上涌起;冯·卡门撞击坑极有可能穿透了该区域的整个月壳,并挖掘出了深部月幔的物质;该区域南部月壳厚度较薄小于5 km,北部平均月壳厚度在15~20 km,月壳平均密度为2 630 kg·m-3,比背面高地月壳密度高,且平均孔隙度为9%,低于月球的平均孔隙度12%。 相似文献
62.
Yu.A. Surkov 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(8):21-38
In this report the main results of the study of radioactivity of the solar sistem bodies are considered. The radioactivity of the Moon and planets was measured by means of vehicles in situ. The radioactivity of the lunar samples, brought to the Earth was studied with laboratory equipment. 相似文献
63.
介绍了成都飞机工业公司的CIMSCAD/CAM集成系统的设计和开发,论证了实现CAD/CAPP/CAM集成的数据转换接口、加工特征定义、CAPP、工程数据库等关键技术的开发和应用。 相似文献
64.
65.
Vladimir Pines Marianna ZlatkowskiArnon Chait 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
In this paper we re-examined the fundamental physics of charging of a dust particle in the moon environment by tenuous anisotropic solar wind plasma. The majority of work on dusty (complex) plasmas is largely concerns with laboratory plasmas, in which charging process of dust grains is very fast, thus making practical the working concept of dynamically equilibrium floating potential and grain charge. However, solar wind plasma parameters are considerably different at the moon orbit, and we found the characteristic charging time of lunar dust grains to be considerably longer, ranging from 3 to 4.6 min for micron size particles, and up to 7.6 h for 10-nm grains, depending on the value of plasma streaming velocity. These findings make it clear that the transient stage of charging process is important in the moon environment, and equilibrium floating potential and grain charge could be considered as long time asymptotic values. For this reason we re-formulated the moon dust charging process as an inherently time-dependent problem and derived the time-dependent charging equation for the grain potential for general case of anisotropic solar wind plasma. Using the results of our kinetics analysis we found that the distribution of charge density over grain surface submerged into solar wind plasma is highly anisotropic, thus making the OML model, which is based on the assumption of isotropic distribution of surface charge density, not applicable to the grain charging problem by the solar wind plasma. 相似文献
66.
67.
A lunar L2-Farside exploration and science mission concept with the Orion Multi-Purpose Crew Vehicle and a teleoperated lander/rover 总被引:1,自引:0,他引:1
Jack O. Burns David A. Kring Joshua B. Hopkins Scott Norris T. Joseph W. Lazio Justin Kasper 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2013
A novel concept is presented in this paper for a human mission to the lunar L2 (Lagrange) point that would be a proving ground for future exploration missions to deep space while also overseeing scientifically important investigations. In an L2 halo orbit above the lunar farside, the astronauts aboard the Orion Crew Vehicle would travel 15% farther from Earth than did the Apollo astronauts and spend almost three times longer in deep space. Such a mission would serve as a first step beyond low Earth orbit and prove out operational spaceflight capabilities such as life support, communication, high speed re-entry, and radiation protection prior to more difficult human exploration missions. On this proposed mission, the crew would teleoperate landers/rovers on the unexplored lunar farside, which would obtain samples from the geologically interesting farside and deploy a low radio frequency telescope. Sampling the South Pole-Aitken basin, one of the oldest impact basins in the solar system, is a key science objective of the 2011 Planetary Science Decadal Survey. Observations at low radio frequencies to track the effects of the Universe’s first stars/galaxies on the intergalactic medium are a priority of the 2010 Astronomy and Astrophysics Decadal Survey. Such telerobotic oversight would also demonstrate capability for human and robotic cooperation on future, more complex deep space missions such as exploring Mars. 相似文献
68.
Ouyang Ziyuan Li Chunlai Zou Yongliao Zhang Hongbo Lu Chang Liu Jianzhong Liu Jianjun Zuo Wei Su Yan Wen Weibin Bian Wei Zhao Baochang Wang Jianyu Yang Jianfeng Chang Jin Wang Huanyu Zhang Xiaohui Wang Shijin Wang Min Ren Xin Mu Lingli Kong Deqing Wang Xiaoqian Wang Fang Geng Liang Zhang Zhoubin Zheng Lei Zhu Xinying Zheng Yongchun Li Junduo Zou Xiaoduan Xu Chun Shi Shuobiao Gao Yifei Gao Guannan 《空间科学学报》2010,30(5):392-403
Chang'E-1 is the first lunar mission in China, which was successfully launched on Oct. 24th, 2007. It was guided to crash on the Moon on March 1, 2009, at 52.36oE, 1.50oS, in the north of Mare Fecunditatis. The total mission lasted 495 days, exceeding the designed life-span about four months. 1.37 Terabytes raw data was received from Chang'E-1. It was then processed into 4 Terabytes science data at different levels. A series of science results have been achieved by analyzing and applicating these data, especially "global image of the Moon of China's first lunar exploration mission'. Four scientific goals of Chang'E-1 have been achieved. It provides abundant materials for the research of lunar sciences and cosmochemistry. Meanwhile these results will serve for China's future lunar missions. 相似文献
69.
月球表面粗糙度的分形表征 总被引:2,自引:0,他引:2
文中采用"嫦娥一号"卫星探测器返回的激光高程计的数据,从研究月球表面的分形特征出发,选取月球表面的湿海区域进行研究,通过对激光高度计的原始数据进行处理,并利用SPSS统计软件对这两组数据进行拟合得到最佳的拟合模型。结果指出:1)分维可以作为一个独立的表征参量来表征粗糙表面的平缓程度。2)由拟合结果图可知,对于月球表面的湿海区域,分维与粗糙度存在单调递增关系,即分维值越大,区域表面越粗糙,表面起伏变化也越剧烈;并通过分析得出湿海区域的地形起伏较大。3)通过分维值D与粗糙度之间的关系式,对于某区域的任意一段轮廓,可以通过计算分维值D得出该轮廓的粗糙度值。同样的,对任一粗糙度值,可以求出相应的分维值以及该轮廓的具体纬度值位置。4)对于月球表面的其他区域,同样可以得出他们之间的相关性,从而达到研究月表地貌演化过程的目的。 相似文献
70.
Y. Saito M.N. Nishino S. Yokota H. Tsunakawa M. Matsushima F. Takahashi H. Shibuya H. Shimizu 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
In the Earth’s magnetotail, Japanese Moon orbiter Kaguya repeatedly encountered the plasmoid or plasma sheet. The encounters were characterized by the low energy ion signatures including lobe cold ions, cold ion acceleration in the plasma sheet-lobe boundaries, and hot plasma sheet ions or fast flowing ions associated with plasmoids. Different from the previous observations made in the magnetotail by the GEOTAIL spacecraft, the ions were affected by the existence of the Moon. On the dayside of the Moon, tailward flowing cold ions and their acceleration were observed. However, on the night side, tailward flowing cold ions could not be observed since the Moon blocked them. In stead, ion acceleration by the spacecraft potential and the electron beam accelerated by the potential difference between lunar surface and spacecraft were simultaneously observed. These electron and ion data enabled us to determine the night side lunar surface potential and spacecraft potential only from the observed data for the first time. 相似文献