The exploration of asteroids has received increasing attention since the 1990s because of the unique information these objects contain about the history of the early solar system.Quasi-satellites are a population of a...The exploration of asteroids has received increasing attention since the 1990s because of the unique information these objects contain about the history of the early solar system.Quasi-satellites are a population of asteroids that co-orbit closely with,but are outside the gravitational control of,the planet.So far,only five Earth quasi-satellites have been recognized,among which(469219)Kamo’oalewa(provisionally designated as 2016 HO3)is currently considered the most stable and the closest of these.However,little is known about this particular asteroid or this class of near-Earth asteroids because of the difficulties of observing them.China has announced that Tianwen-2,the asteroid sample-return mission to Kamo’oalewa,will be launched in 2025.Here,we review the current knowledge of Kamo’oalewa in terms of its physical characteristics,dynamic evolution,surface environment,and origin,and we propose possible breakthroughs that the samples could bring concerning the asteroid Kamo’oalewa as an Earth quasi-satellite.Confirming the origin of Kamo’oalewa,from its prevailing provenance as debris of the Moon,could be a promising start to inferring the evolutionary history of the Moon.This history would probably include a more comprehensive view of the lunar farside and the origin of the asymmetry between the two sides of the Moon.Comparing the samples from the Moon and Kamo’oalewa would also provide new insights into the Earth wind.展开更多
1 If astronauts want to stay on the Moon for more than a few days,they must find local resources,and water is one of the most crucial ones.Scientists believe there's water on the Moon,but they're unsure of whe...1 If astronauts want to stay on the Moon for more than a few days,they must find local resources,and water is one of the most crucial ones.Scientists believe there's water on the Moon,but they're unsure of where it lies.2 Two probes are on their way to the Moon to solve this mystery.They will be launched on the same SpaceX Falcon 9 rocket from Cape Canaveral.If everything goes as planned,the first probe to reach the Moon will be Athena.Timothy Crain,the chief technology officer of Intuitive Machines,says it will take about 3 to 4 days,depending on the launch time.They'll orbit the Moon for 2 to 3 days to wait for the Sun to reach the landing site,because the lander's solar panels need sunlight to generate power.It only takes about 15 minutes to land softly after the engine is started.展开更多
我们可能在英语影视剧、文学作品中看到过一个短语叫“once in ablue moon”,这个短语用来描述很少发生的事件或情况,意味着某件事非常罕见,你可能很长时间都遇不到一次。例如,如果一个人偶尔玩一次游戏,你可以说他们“play games once ...我们可能在英语影视剧、文学作品中看到过一个短语叫“once in ablue moon”,这个短语用来描述很少发生的事件或情况,意味着某件事非常罕见,你可能很长时间都遇不到一次。例如,如果一个人偶尔玩一次游戏,你可以说他们“play games once in a blue moon”。展开更多
E·E卡明斯是美国20世纪现代主义诗人的杰出代表。他的诗歌创作在内容和形式上置传统于不顾,以其独特的创作技巧闻名于世。其新奇怪异的诗歌风格为许多研究者所关注。本文试图从in Just和MOOn Over TOwns MOOn两首诗入手,探析他诗...E·E卡明斯是美国20世纪现代主义诗人的杰出代表。他的诗歌创作在内容和形式上置传统于不顾,以其独特的创作技巧闻名于世。其新奇怪异的诗歌风格为许多研究者所关注。本文试图从in Just和MOOn Over TOwns MOOn两首诗入手,探析他诗歌中表现的生态意识,通过卡明斯对爱、春天与自由的歌颂来领略诗人的生态意识,深入领会诗歌的意义。展开更多
To ensure the safety of consumers, prolong the shelf life of moon cake and reduce the cost of manufacturing and marketing enterprises, the optimization of preservative formula and the shelf life of cantonese style moo...To ensure the safety of consumers, prolong the shelf life of moon cake and reduce the cost of manufacturing and marketing enterprises, the optimization of preservative formula and the shelf life of cantonese style moon cake were studied. Through single and compound formula preservative test, the results showed that potassium sorbate and sodium dehydroacetate could inhibit the microorganisms in the moon cake, but the inhibitory effect of sodium dehydroacetate was stronger than that of potassium sorbate; and the combination of potassium sorbate and sodium dehydroacetate had a synergistic effect, and the best formula is 'potassium sorbate 0.44 g/kg mixed with sodium dehydroacetate 0.38 g/kg. A batch of moon cake was prepared with the best preservative formula, then the total number of colonies, molds and coliform group in the samples were detected by random sampling at irregular intervals. The total number of molds exceeded the limit on the 187^th d, and it indicated that the shelf life of the product was 187 d. Compared with the conventional 15-day shelf life, this research greatly prolongs the sheff life of cantonese style moon cake, and cut down the cost of moon cake enterprises. It is worthy of popularization and application.展开更多
Image is an abnormal description of a word or phrase used to create artistic conception in classical poem writing.This paper focuses on the literal meaning of image and symbolic meaning of the moon by analyzing typica...Image is an abnormal description of a word or phrase used to create artistic conception in classical poem writing.This paper focuses on the literal meaning of image and symbolic meaning of the moon by analyzing typical moon-chanting poems of Li Bai,to illustrate the role of image in ancient poetry writing.展开更多
To better understand Earth's present tectonic style-plate tectonics—and how it may have evolved from single plate(stagnant lid) tectonics, it is instructive to consider how common it is among similar bodies in th...To better understand Earth's present tectonic style-plate tectonics—and how it may have evolved from single plate(stagnant lid) tectonics, it is instructive to consider how common it is among similar bodies in the Solar System. Plate tectonics is a style of convection for an active planetoid where lid fragment(plate) motions reflect sinking of dense lithosphere in subduction zones, causing upwelling of asthenosphere at divergent plate boundaries and accompanied by focused upwellings, or mantle plumes;any other tectonic style is usefully called "stagnant lid" or "fragmented lid". In 2015 humanity completed a 50+ year effort to survey the 30 largest planets, asteroids, satellites, and inner Kuiper Belt objects,which we informally call "planetoids" and use especially images of these bodies to infer their tectonic activity. The four largest planetoids are enveloped in gas and ice(Jupiter, Saturn, Uranus, and Neptune)and are not considered. The other 26 planetoids range in mass over 5 orders of magnitude and in diameter over 2 orders of magnitude, from massive Earth down to tiny Proteus; these bodies also range widely in density, from 1000 to 5500 kg/m^3. A gap separates 8 silicate planetoids with ρ = 3000 kg/m^3 or greater from 20 icy planetoids(including the gaseous and icy giant planets) with ρ = 2200 kg/m^3 or less. We define the "Tectonic Activity Index"(TAI), scoring each body from 0 to 3 based on evidence for recent volcanism, deformation, and resurfacing(inferred from impact crater density). Nine planetoids with TAI = 2 or greater are interpreted to be tectonically and convectively active whereas 17 with TAI <2 are inferred to be tectonically dead. We further infer that active planetoids have lithospheres or icy shells overlying asthenosphere or water/weak ice. TAI of silicate(rocky) planetoids positively correlates with their inferred Rayleigh number. We conclude that some type of stagnant lid tectonics is the dominant mode of heat loss and that plate tectonics is unusual. To make progress understanding Earth's tectonic history and the tectonic style of active exoplanets, we need to better understand the range and controls of active stagnant lid tectonics.展开更多
The Crescent Moon Spring is a precious natural heritage. However, the dynamic characteristics of megadunes around the Crescent Moon Spring are not well known. This paper quantitatively studied the character- istics an...The Crescent Moon Spring is a precious natural heritage. However, the dynamic characteristics of megadunes around the Crescent Moon Spring are not well known. This paper quantitatively studied the character- istics and changes of megadunes around the Crescent Moon Spring by interpreting aerial photographs taken in 1985 and 2004 and analysing the dune crestlines and the wind data collected from 2011 to 2012. Results revealed that pyramid dunes were formed by a complex wind regime. The Crescent Moon Spring was not buried by shifting sands because of the stable wind regime and relative stability of pyramid dunes. The crestlines of the dunes around the spring moved northward between 1985 and 2004. The south-facing slip faces were also exposed to wind ero- sion, whereas the other faces were under deposition, thus indicating that the southerly wind was relatively en- hanced. Limiting the scale of tall windbreaks and architectures in the Dunhuang oasis at the north of the spring was necessary to maintain the dynamic equilibrium of the wind regime and sand transport.展开更多
Based on the CCD images,IIM data and DEM data of China's lunar exploration project (Chang'E-Ⅰ) and related processed and analytic results,an integrated study of regional geology of Sinus Iridum and its adjacent a...Based on the CCD images,IIM data and DEM data of China's lunar exploration project (Chang'E-Ⅰ) and related processed and analytic results,an integrated study of regional geology of Sinus Iridum and its adjacent area was conducted,and a series of relevant researches and analyses were carried out,including analysis of impact craters and their extrusive and accumulative materials,division of stratigraphic and tectonic units and classification of rock types,integrated analysis of chronology and lunar evolution history.In consideration of crater's shape features,quantity and preserving status of filling materials,the lunar impact craters can be divided into 7 types and 11 subtypes,and the accumulative materials of craters are divided into 6 types and 9 accumulative groups.According to the content and distribution of TiO2 and image characteristics,the basalts are divided into high-TiO2,medium-TiO2 and low-TiO2 basalts.Discussion was made on division of tectonic units and evolution features in the study area.The geological map of the Sinus Iridum Quadrangle (LQ-4) at a scale of 1∶2.5 M was preliminarily compiled with the ArcGIS system,and the spatial database of the map was established.Related technical specification,procedure and method for lunar geological mapping have been worked out,so as to lay a foundation for the forthcoming geological mapping of the global Moon in China by using the data of Chang'E-Ⅱ and also for comprehensive study and geological mapping of other celestial bodies in the future.展开更多
After a quick visit to the Moon in December 2020,China’s Chang'e 5 mission has delivered back to Earth the first new specimens of lunar rock and soil since 1976[1].Scooped from a volcanic location not sampled bef...After a quick visit to the Moon in December 2020,China’s Chang'e 5 mission has delivered back to Earth the first new specimens of lunar rock and soil since 1976[1].Scooped from a volcanic location not sampled before,the material may provide insights into the Moon's evolution and the history of the solar system.The mission also demonstrates a new level of technical sophistication for the Chinese space program and provides a blueprint for future expeditions to return samples from other bodies in the solar system,said Jim Head,a professor of geological sciences at Brown University in Providence,RI,USA.展开更多
The aim of this paper is to continue analyzing the interactions in the three-body system made up of the Sun, the Moon, and the Earth. First, we review new details about Moon-Earth connections, with a special focus on ...The aim of this paper is to continue analyzing the interactions in the three-body system made up of the Sun, the Moon, and the Earth. First, we review new details about Moon-Earth connections, with a special focus on mechanical forces. Following, we expand the study to consider the pair Sun-Earth, with calculations for electromagnetic forces. The objective in both cases is to know how mechanical and electromagnetic forces affect seismological events on Earth. Our calculations found that Solar Cycles have no direct interaction with earthquake variations. Instead, we established that there is an internal discrepancy for quakes below 35 km detected in some of the regions analyzed. The results indicate that geomagnetic variations must be studied next to understand their connections to earthquakes.展开更多
Marius Hills is a volcanic plateau on the nearside of the Moon. It is of great interest for its high concentration of volcanic features, including domes, cones, ridges, and rilles. However, the morphological and chron...Marius Hills is a volcanic plateau on the nearside of the Moon. It is of great interest for its high concentration of volcanic features, including domes, cones, ridges, and rilles. However, the morphological and chronological characteristics of this plateau were not well studied due to the low resolution of early mission data. This study describes the detailed morphology of the volcanic features using the latest high spatial resolution images of the Terrain Camera (TC) onboard Selene-1 (10 m/pix) and Narrow Angle Camera (NAC) onboard the Lunar Reconnaissance Orbiter (LRO) (0.5 m/pix). We report here some new structures such as skylights and remnants of lava tubes. We have divided spectrally homogenous areas with Clementine UVVIS data and did crater size frequency distribution (CSFD) measurements with Lunar Orbiter (LO) IV and TC images in every spectral unit. We first report absolute model ages of 1.10 Ga for Marius basalt 1, 1.49 Ga for Fiamsteed basalt, and 1.46 Ga for Schiaparelli Basalt. In addition, we have identified several younger lava events: they are Marius basalt 2 (814 Ma), medium to low titanium basalt (949 Ma), and undifferentiated medium titanium basalt (687 Ma). Finally, we propose a mantle plume scenario for the formation of Marius Hills, which could solve the inconsistency of previous models.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.42241106 and 42388101).
文摘The exploration of asteroids has received increasing attention since the 1990s because of the unique information these objects contain about the history of the early solar system.Quasi-satellites are a population of asteroids that co-orbit closely with,but are outside the gravitational control of,the planet.So far,only five Earth quasi-satellites have been recognized,among which(469219)Kamo’oalewa(provisionally designated as 2016 HO3)is currently considered the most stable and the closest of these.However,little is known about this particular asteroid or this class of near-Earth asteroids because of the difficulties of observing them.China has announced that Tianwen-2,the asteroid sample-return mission to Kamo’oalewa,will be launched in 2025.Here,we review the current knowledge of Kamo’oalewa in terms of its physical characteristics,dynamic evolution,surface environment,and origin,and we propose possible breakthroughs that the samples could bring concerning the asteroid Kamo’oalewa as an Earth quasi-satellite.Confirming the origin of Kamo’oalewa,from its prevailing provenance as debris of the Moon,could be a promising start to inferring the evolutionary history of the Moon.This history would probably include a more comprehensive view of the lunar farside and the origin of the asymmetry between the two sides of the Moon.Comparing the samples from the Moon and Kamo’oalewa would also provide new insights into the Earth wind.
文摘1 If astronauts want to stay on the Moon for more than a few days,they must find local resources,and water is one of the most crucial ones.Scientists believe there's water on the Moon,but they're unsure of where it lies.2 Two probes are on their way to the Moon to solve this mystery.They will be launched on the same SpaceX Falcon 9 rocket from Cape Canaveral.If everything goes as planned,the first probe to reach the Moon will be Athena.Timothy Crain,the chief technology officer of Intuitive Machines,says it will take about 3 to 4 days,depending on the launch time.They'll orbit the Moon for 2 to 3 days to wait for the Sun to reach the landing site,because the lander's solar panels need sunlight to generate power.It only takes about 15 minutes to land softly after the engine is started.
文摘E·E卡明斯是美国20世纪现代主义诗人的杰出代表。他的诗歌创作在内容和形式上置传统于不顾,以其独特的创作技巧闻名于世。其新奇怪异的诗歌风格为许多研究者所关注。本文试图从in Just和MOOn Over TOwns MOOn两首诗入手,探析他诗歌中表现的生态意识,通过卡明斯对爱、春天与自由的歌颂来领略诗人的生态意识,深入领会诗歌的意义。
基金Supported by Project of the Department of Education of Fujian Province(JB13317)~~
文摘To ensure the safety of consumers, prolong the shelf life of moon cake and reduce the cost of manufacturing and marketing enterprises, the optimization of preservative formula and the shelf life of cantonese style moon cake were studied. Through single and compound formula preservative test, the results showed that potassium sorbate and sodium dehydroacetate could inhibit the microorganisms in the moon cake, but the inhibitory effect of sodium dehydroacetate was stronger than that of potassium sorbate; and the combination of potassium sorbate and sodium dehydroacetate had a synergistic effect, and the best formula is 'potassium sorbate 0.44 g/kg mixed with sodium dehydroacetate 0.38 g/kg. A batch of moon cake was prepared with the best preservative formula, then the total number of colonies, molds and coliform group in the samples were detected by random sampling at irregular intervals. The total number of molds exceeded the limit on the 187^th d, and it indicated that the shelf life of the product was 187 d. Compared with the conventional 15-day shelf life, this research greatly prolongs the sheff life of cantonese style moon cake, and cut down the cost of moon cake enterprises. It is worthy of popularization and application.
文摘Image is an abnormal description of a word or phrase used to create artistic conception in classical poem writing.This paper focuses on the literal meaning of image and symbolic meaning of the moon by analyzing typical moon-chanting poems of Li Bai,to illustrate the role of image in ancient poetry writing.
基金supported by SNSF grant IZKOZ-2_154380partly supported by SNF 200021_149252
文摘To better understand Earth's present tectonic style-plate tectonics—and how it may have evolved from single plate(stagnant lid) tectonics, it is instructive to consider how common it is among similar bodies in the Solar System. Plate tectonics is a style of convection for an active planetoid where lid fragment(plate) motions reflect sinking of dense lithosphere in subduction zones, causing upwelling of asthenosphere at divergent plate boundaries and accompanied by focused upwellings, or mantle plumes;any other tectonic style is usefully called "stagnant lid" or "fragmented lid". In 2015 humanity completed a 50+ year effort to survey the 30 largest planets, asteroids, satellites, and inner Kuiper Belt objects,which we informally call "planetoids" and use especially images of these bodies to infer their tectonic activity. The four largest planetoids are enveloped in gas and ice(Jupiter, Saturn, Uranus, and Neptune)and are not considered. The other 26 planetoids range in mass over 5 orders of magnitude and in diameter over 2 orders of magnitude, from massive Earth down to tiny Proteus; these bodies also range widely in density, from 1000 to 5500 kg/m^3. A gap separates 8 silicate planetoids with ρ = 3000 kg/m^3 or greater from 20 icy planetoids(including the gaseous and icy giant planets) with ρ = 2200 kg/m^3 or less. We define the "Tectonic Activity Index"(TAI), scoring each body from 0 to 3 based on evidence for recent volcanism, deformation, and resurfacing(inferred from impact crater density). Nine planetoids with TAI = 2 or greater are interpreted to be tectonically and convectively active whereas 17 with TAI <2 are inferred to be tectonically dead. We further infer that active planetoids have lithospheres or icy shells overlying asthenosphere or water/weak ice. TAI of silicate(rocky) planetoids positively correlates with their inferred Rayleigh number. We conclude that some type of stagnant lid tectonics is the dominant mode of heat loss and that plate tectonics is unusual. To make progress understanding Earth's tectonic history and the tectonic style of active exoplanets, we need to better understand the range and controls of active stagnant lid tectonics.
基金funded by the National Key Technology R&D Program of China (2013BAC07B02)the National Natural Science Foundation of China (41071009)the West Light Foundation of Chinese Academy of Sciences (29Y128841)
文摘The Crescent Moon Spring is a precious natural heritage. However, the dynamic characteristics of megadunes around the Crescent Moon Spring are not well known. This paper quantitatively studied the character- istics and changes of megadunes around the Crescent Moon Spring by interpreting aerial photographs taken in 1985 and 2004 and analysing the dune crestlines and the wind data collected from 2011 to 2012. Results revealed that pyramid dunes were formed by a complex wind regime. The Crescent Moon Spring was not buried by shifting sands because of the stable wind regime and relative stability of pyramid dunes. The crestlines of the dunes around the spring moved northward between 1985 and 2004. The south-facing slip faces were also exposed to wind ero- sion, whereas the other faces were under deposition, thus indicating that the southerly wind was relatively en- hanced. Limiting the scale of tall windbreaks and architectures in the Dunhuang oasis at the north of the spring was necessary to maintain the dynamic equilibrium of the wind regime and sand transport.
基金financially supported by the National "863" Project (Grant No.:2010AA12220105)the Standard Research of Lunar mapping of Geology and Tectonics (Grant No.:Y2ZZ031000-02) from Institute of Geochemistry, Chinese Academy of Sciences
文摘Based on the CCD images,IIM data and DEM data of China's lunar exploration project (Chang'E-Ⅰ) and related processed and analytic results,an integrated study of regional geology of Sinus Iridum and its adjacent area was conducted,and a series of relevant researches and analyses were carried out,including analysis of impact craters and their extrusive and accumulative materials,division of stratigraphic and tectonic units and classification of rock types,integrated analysis of chronology and lunar evolution history.In consideration of crater's shape features,quantity and preserving status of filling materials,the lunar impact craters can be divided into 7 types and 11 subtypes,and the accumulative materials of craters are divided into 6 types and 9 accumulative groups.According to the content and distribution of TiO2 and image characteristics,the basalts are divided into high-TiO2,medium-TiO2 and low-TiO2 basalts.Discussion was made on division of tectonic units and evolution features in the study area.The geological map of the Sinus Iridum Quadrangle (LQ-4) at a scale of 1∶2.5 M was preliminarily compiled with the ArcGIS system,and the spatial database of the map was established.Related technical specification,procedure and method for lunar geological mapping have been worked out,so as to lay a foundation for the forthcoming geological mapping of the global Moon in China by using the data of Chang'E-Ⅱ and also for comprehensive study and geological mapping of other celestial bodies in the future.
文摘After a quick visit to the Moon in December 2020,China’s Chang'e 5 mission has delivered back to Earth the first new specimens of lunar rock and soil since 1976[1].Scooped from a volcanic location not sampled before,the material may provide insights into the Moon's evolution and the history of the solar system.The mission also demonstrates a new level of technical sophistication for the Chinese space program and provides a blueprint for future expeditions to return samples from other bodies in the solar system,said Jim Head,a professor of geological sciences at Brown University in Providence,RI,USA.
文摘The aim of this paper is to continue analyzing the interactions in the three-body system made up of the Sun, the Moon, and the Earth. First, we review new details about Moon-Earth connections, with a special focus on mechanical forces. Following, we expand the study to consider the pair Sun-Earth, with calculations for electromagnetic forces. The objective in both cases is to know how mechanical and electromagnetic forces affect seismological events on Earth. Our calculations found that Solar Cycles have no direct interaction with earthquake variations. Instead, we established that there is an internal discrepancy for quakes below 35 km detected in some of the regions analyzed. The results indicate that geomagnetic variations must be studied next to understand their connections to earthquakes.
基金supported by the National Natural Science Foundation of China (Nos. 41072045, 41102209)the Research Fund for the Doctoral Program of Higher Education (No. 20090145110001)+1 种基金Nondestructive Analysis Technique and Best Analysis Scheme of Lunar Sample (No. TY3Q20110029)China University of Geosciences (Wuhan) GF Special Research Fund (No. CUGXGF0901)
文摘Marius Hills is a volcanic plateau on the nearside of the Moon. It is of great interest for its high concentration of volcanic features, including domes, cones, ridges, and rilles. However, the morphological and chronological characteristics of this plateau were not well studied due to the low resolution of early mission data. This study describes the detailed morphology of the volcanic features using the latest high spatial resolution images of the Terrain Camera (TC) onboard Selene-1 (10 m/pix) and Narrow Angle Camera (NAC) onboard the Lunar Reconnaissance Orbiter (LRO) (0.5 m/pix). We report here some new structures such as skylights and remnants of lava tubes. We have divided spectrally homogenous areas with Clementine UVVIS data and did crater size frequency distribution (CSFD) measurements with Lunar Orbiter (LO) IV and TC images in every spectral unit. We first report absolute model ages of 1.10 Ga for Marius basalt 1, 1.49 Ga for Fiamsteed basalt, and 1.46 Ga for Schiaparelli Basalt. In addition, we have identified several younger lava events: they are Marius basalt 2 (814 Ma), medium to low titanium basalt (949 Ma), and undifferentiated medium titanium basalt (687 Ma). Finally, we propose a mantle plume scenario for the formation of Marius Hills, which could solve the inconsistency of previous models.