Olivine-norite rock detected by the lunar rover Yutu-2 likely crystallized from the SPA-impact melt pool

Chang’E-4 landed in the South Pole-Aitken (SPA) basin, providing a unique chance to probe the composition of the lunar interior. Its landing site is located on ejecta strips in Von Kármán crater that possibly originate from the neighboring Finsen crater. A surface rock and the lunar regolith at 10 sites along the rover Yutu-2 track were measured by the onboard Visible and Near-Infrared Imaging Spectrometer in the first three lunar days of mission operations. In situ spectra of the regolith have peak band positions at 1 and 2 μm, similar to the spectral data of Finsen ejecta from the Moon Mineralogy Mapper, which confirms that the regolith''s composition of the landing area is mostly similar to that of Finsen ejecta. The rock spectrum shows similar band peak positions, but stronger absorptions, suggesting relatively fresh exposure. The rock may consist of 38.1 ± 5.4% low-Ca pyroxene, 13.9 ± 5.1% olivine and 48.0 ± 3.1% plagioclase, referred to as olivine-norite. The plagioclase-abundant and olivine-poor modal composition of the rock is inconsistent with the origin of the mantle, but representative of the lunar lower crust. Alternatively, the rock crystallized from the impact-derived melt pool formed by the SPA-impact event via mixing the lunar crust and mantle materials. This scenario is consistent with fast-cooling thermal conditions of a shallow melt pool, indicated by the fine to medium-sized texture (<3 mm) of the rock and the SPA-impact melting model [Icarus 2012; 220: 730–43].     

Isotopic evidence for volatile replenishment of the Moon during the Late Accretion

The traditional view of a dry, volatile-poor Moon has been challenged by the identification of water and other volatiles in lunar samples, but the volatile budget delivery time(s), source(s) and temporal evolution remain poorly constrained. Here we show that hydrogen and chlorine isotopic ratios in lunar apatite changed significantly during the Late Accretion (LA, 4.1–3.8 billion years ago). During this period, deuterium/hydrogen ratios in the Moon changed from initial carbonaceous-chondrite-like values to values consistent with an influx of ordinary-chondrite-like material and pre-LA elevated δ³⁷Cl values drop towards lower chondrite-like values. Inferred pre-LA lunar interior water contents are significantly lower than pristine values suggesting degassing, followed by an increase during the LA. These trends are consistent with dynamic models of solar-system evolution, suggesting that the Moon''s (and Earth''s) initial volatiles were replenished ∼0.5 Ga after their formation, with their final budgets reflecting a mixture of sources and delivery times.     

Characteristics of the lunar samples returned by the Chang'E-5 mission

Forty-five years after the Apollo and Luna missions returned lunar samples,China's Chang'E-5(CE-5)mission collected new samples from the mid-latitude region in ...     

China's lunar and deep space exploration: touching the moon and exploring the universe

The Chinese lunar probe Chang''e-4 (CE-4) landed in the Von Kármán crater within the South Pole–Aitken (SPA) basin on the far-side of the Moon on 3 January 2019. Following this, the moon rover Yutu-2 separated from the CE-4 lander and started its travels and exploration on the far-side of the Moon. Before this landing, humans had remotely observed the far-side of the Moon with lunar satellites. However, it was the first time that a man-made spacecraft had landed there and actually left behind wheel prints belonging to humanity.Since China''s Lunar Exploration Project (CLEP), or Chang''e Project, started in 2004, China has accomplished the first two steps of its three-step plan of ‘Orbiting, Landing and Returning’. CE-3 and CE-4 landed successfully on the near-side and far-side of the Moon, respectively. In the near future, CE-5 will land again on the near-side of the Moon and take lunar rock and soil samples back to Earth, thus completing the three-step plan of CLEP. In April 2019, National Science Review (NSR) interviewed three key figures of CLEP: CLEP Chief Engineer Weiren Wu (), the first CLEP Chief Scientist and CLEP senior consultant Ziyuan Ouyang (), and CLEP third phase Vice-Chief Engineer, CE-4 Ground Research and Application System Director Chunlai Li (). They talked about the scientific expectations and future plans of China''s lunar and deep space exploration.     

月球表面岩石类型的分布特征：基于Lunar Prospector（LP）伽马射线谱仪探测数据的反演

Apollo和LP伽马射线谱仪获取了全月10种元素的分布图,通过已有的月岩以及陨石的化学成分数据,将伽马射线谱仪探测数据与这些数据融合,用Th-Fe-Mg三角图解定性的获得元素含量与岩石类型的相关性,同时通过以前融合的数据,获得了月海玄武岩、月陆斜长岩、KREEP岩和富镁岩的全月球表面岩石类型分布图.     

VLBI network： A security net for lunar exploration

1 March, 2009 witnesses the solemn, spectacular and somewhat sad ending of the lunar flight of Chang＇e-1. After orbiting the Moon for 494 days,the first China-made lunar orbiter, named after a beautiful fairy in Chinese mythology, culminates her perfect journey with a last dance, a controlled crash to lunar surface at 1.50°S 52.36°E at 16：13 GMT＋8.     

月球探测的进展与我国的月球探测

月球探测是我国航天活动发展的必然选择，将成为我国航天事业的第 三个里程碑，自20世纪60—70年代的第一次月球探测高潮后，迎来了“重返月球”的又一次 月球探 测热潮，以开发利用月球上丰富的核聚变燃料氦3、矿产和空间环境资源等为最终目标。 我国已经具备了进行月球探测的技术能力，首期工程的科学目标包括获取月球表面三维影像\\r 、分析月球表面有用元素含量和物质类型的分布特点、探测月壤厚度和探测地月空间环境 。     

绕月探测工程科学应用研究进展

我国月球探测工程分为“绕、落、回”三期实施。其中一期即绕月探测工程,其主要科学探测任务是对月球开展全球性、整体性和综合性的科学探测．包括以下4项科学目标：获取月球表面三维立体影像;分析月球表面元素含量和物质类型的分布特点;探测月壤特性;探测地月空间环境。在这4个科学目标中以全月球数字地图和三维立体影像图的获取为重点目标,结合物质成分探测、月壤特性探测和空间环境探测的成果,既与国际月球探测的发展趋势接轨,又有自己的创新特色。本文将主要介绍中科院在绕月探测工程中主要获得的科学研究成果。     

Lunar outpost agriculture

America's long-term commitment to a new Space Exploration Initiative has focused attention on the basic requirements for establishing a permanently manned lunar outpost and, ultimately, a martian one. High among these is the development of Regenerative Life Support Systems--with lunar agriculture an essential component--to provide a high level of self-sufficiency.     

Thermophysical properties of the regolith on the lunar far side revealed by the in situ temperature probing of the Chang’E-4 mission

Temperature probes onboard the Chang’E-4 (CE-4) spacecraft provide the first in situ regolith temperature measurements from the far side of the Moon. We present these temperature measurements with a customized thermal model and reveal the particle size of the lunar regolith at the CE-4 landing site to be ∼15 μm on average over depth, which indicates an immature regolith below the surface. In addition, the conductive component of thermal conductivity is measured as ∼1.53 × 10^–3 W m^–1 K^–1 on the surface and ∼8.48 × 10^–3 W m^–1 K^–1 at a depth of 1 m. The average bulk density is ∼471 kg m^–3 on the surface and ∼824 kg m^–3 in the upper 30 cm of the lunar regolith. These thermophysical properties provide important additional ‘ground truth’ at the lunar far side, which is critical for the future analysis and interpretation of global temperature observations.     

“嫦娥三号”任务及其初步科学成果

"嫦娥三号"月球探测器自2013年12月成功着陆月球之后,已在月球停留超过3年时间,创下在月球表面工作时间最长的世界纪录。与此同时,"嫦娥三号"探测器搭载的8台科学载荷获得了大量的科学探测数据。为推进"嫦娥三号"任务科学探测数据的应用和研究,力争出好成果、快出成果,中科院在"嫦娥三号"任务执行前集中全国优势力量组建了由科学家、科学载荷研制单位技术人员和负责科学探测数据处理的地面应用系统技术人员组成的5个科学应用核心团队,并设立"‘嫦娥三号’任务探测数据科学应用研究"重点部署项目。经过两年多的时间,"嫦娥三号"任务核心科学家团队在月球地形地貌、浅表层地质结构、月基天文观测以及地球等离子体观测等方面取得了一系列创新性研究成果。     

宋代的日食食限算法

宋代历法中记载了多种日食食限和判定日食的方法,直到《纪元历》,这些方法才最终得到完善和定型。中国古代历算家很可能首先知道了春分日正午时刻的月亮视差,然后通过修正得到任意时刻的月亮视差,来解决月亮视差对日食的计算问题。《纪元历》以前的唐宋历法通过推算月亮在黄道内外来判断有无日食,从《纪元历》开始,历法中才使用食甚时刻视月亮到视黄白交点的距离来定义食限。中国古代阴阳历食限不相等的原因是：历法家首先给出阳历食限,即春分正午时真黄白交点到视黄白交点的距离,约为6度,然后定出阴历食限,约为8度。     

China unveils its first full image of the Moon

The country＇s first full map of the Moon has recently been released by theState Administration of Science, Technology and Industry for National Defense. The image, which was produced on the basis of data obtained by the Chang＇e-1, China＇s first lunar probe, over the past one year or so, was presented to the National Museum of China on 12 November, 2008, in Beijing.     

China Gears up for Lunar Science

China is getting ready for a sample return mission later this year and soft landing on the far side of the Moon next year, which will complete the nation's unmanned lunar exploration program and bring more scientific returns to researchers.     

Sicily or the Sea of Tranquility? Mapping and naming the moon

In their race to provide the ultimate guide to the moon, two 17th-century astronomers proposed lunar maps and nomenclatures that they hoped would gain international currency. But the names we use today were those proposed by the Jesuit, a friend of Galileo's persecutors, in a book whose purpose was to refute the Copernican system once and for all. We now believe that Riccioli was wrong about the universe, but why do we still use his nomenclature? The keys to this foundational visual debate in astronomical image-making are the moon maps themselves.     

Water-clocks and time measurement in classical antiquity

The water-clock was the first mechanical device for time measurement to be used by the Greeks. Previously they had relied on sundials, or observation of the phases of the moon or the position of the sun in the zodiac to locate points of time within the day, month or year; and by the mid-fifth century BC they had made some progress with the difficult calendar problems due to the fact that the solar day, the lunar month, and the solar year are not commensurable with each other in whole numbers.     

Predicting the past: ancient eclipses and Airy, Newcomb, and Huxley on the authority of science

Greek historical accounts of ancient eclipses were an important, if peculiar, focus of scientific attention in the nineteenth century. Victorian-era astronomers tried to correct the classical histories using scientific methods, then used those histories as data with which to calibrate their lunar theories, then rejected the histories as having any relevance at all. The specific dating of these eclipses--apparently a simple exercise in celestial mechanics--became bound up with tensions between scientific and humanistic approaches to the past as well as with wider social debates over the power and authority of science in general. The major figures discussed here, including G. B. Airy, Simon Newcomb, and T. H. Huxley, argued that the critical question was whether science could speak authoritatively about the past. To them, the ability of science to talk about the past indicated its power to talk about the future; it was also the fulcrum of fierce boundary disputes among science, history, and religion.     

CFM56-3发动机N2转速管理系统原理

CFM56-3系列发动机是由美国通用电气公司(GE)和法国国营航空发动机研制公司(SNECMA)组成的国际公司(CFMI)研制生产的为波音B737-300/400/500型航空器翼吊发动机;其N2转速管理系统为飞机提供精确的燃油控制功能以防止发动机超速及失速情况的发生。N2转速管理系统主要通过接受发动机的核心转子转速(N2)和动力角(PLA)来控制燃油流量使发动机实际转速与目标转速相符。     

黄河下游悬河段断流对沿岸地下水影响评价

黄河下游悬河段地下水系统分布面积29288.27km2,含有两个含水层组.浅层含水层组赋存潜水和微承压水,中深层含水层组赋存承压水;并对含水介质结构、边界条件及地下水流态进行了研究,建立了水文地质概念模型,构建了三维地下水流数学模型.通过对数学模型的识别和验证,进行了悬河段地表水、地下水转化关系的模拟研究:预测了黄河下游在不同的断流时间和断流河段长度下,黄河侧渗量的变化趋势.模拟计算结果表明,花园口站-河口段全年断流时,黄河悬河段无侧渗补给;断流300天时,黄河全年侧渗量为2.98×108m3,较现状年侧渗量减少了52.25%.夹河滩站-河口段全年断流时,黄河全年侧渗量为1.6×108m3,较现状年侧渗量减少了74.4%;断流300天时,黄河全年侧渗量3.46×108m3,较现状年黄河侧渗量减少了44.5%.泺口站-河口段全年断流时,黄河全年侧渗量为4.83×108m3,较现状年黄河侧渗量减少了22.58%;断流300天时,黄河全年侧渗量为5.17×108m3,较现状年黄河侧渗量减少17.06%.利津站-河口段全年断流时,黄河全年侧渗量为6.15×108m3,较现状年黄河侧渗量仅减少1.5%.上述研究为水资源合理开发利用和黄河水量人工实时调控提供了依据.