Analysis of Chang’e-5 lunar core drilling process

Chang’e-5 explorer successfully acquired lunar regolith core samples from depths of greater than 1 m of lunar surface. This study analyzed the lunar core drilling process based on the telemetry data, image information, and returned samples to optimize the sampling device design and enhance the understanding of the lunar regolith. In particular, a prediction method for the projected drilling path and local terrain fitting of drilling dip angle was proposed based on the flight events recorded during the core drilling process and the image information acquired before, during, and after sampling. The results revealed that the drilling dip angle of Chang’e-5 was approximately 2.3°, and the deviation of the drilling length and depth was less than 2 mm. For continuous drilling, a fusion method based on telemetry data and image information was applied to determine the demarcation point of drilling with and without the lunar soil. The position of the demarcation point implied that the drilling point remained at approximately 6 mm loose soil, thereby lagging the action of the force response. Additionally, a characteristic parameter comparison method was proposed for the lunar and ground drilling to analyze the status of the lunar soil. Furthermore, the analysis results revealed that the majority of the Chang’e-5 drilling samples were derived from 0–73.8 cm below the lunar surface and few samples were extracted below 73.8 cm, as the drilling encountered several rocky regions. Moreover, the drilling point exhibited two prominent stratification variations at ～28.7 cm and ～70 cm below the lunar surface. Ultimately, the preliminary relationship between sample dissected position in soft tube and drilling displacement was analyzed. The segmented estimation results can support research on subsurface lunar soil.     

无强波构型理论发展现状研究

本文引入了一种由Busemann超声速双翼理论发展而来的无强激波构型,该构型可明显消弱超声速飞行时带来的波阻和声爆。文中分析了无强波构型的机理和气动特性,介绍了该构型理论研究和应用研究进展,并探讨了该构型在超声速飞行器设计应用中的关键性问题。该理论为未来低声爆超声速飞机的设计提供了一个全新的思路,是未来超声速/高超声速飞行器发展必要的技术基础。     

Gas-dynamic approach to the theory of non-linear ion-acoustic waves in plasma with Kaniadakis’ distributed species

The non-linear theory of ion-acoustic waves in two-spesies isotropic collisionless plasma is developed. Both light electron and heavy ion species in the plasma are distributed with Kaniadakis’ statistics. Kaniadakis’ gas law is derived. The exact formula for the Sagdeev pseudopotential in parametric form is derived by the method based on the integration of the inverse function. The pseudopotential is analyzed. It is shown that periodic ion-acoustic waves and solitons are possible in the studied plasma. The differential equation describing the profile of the ion concentration in the wave is derived. The profiles of this concentration in the periodic ion-acoustic wave and soliton are calculated.     

Space law education in China: Status quo,shortcomings and possible ways out

Space law education has an essential role in the space capacity building of a country because of its importance for human resources development in space law. Comparisons between Canada and China, the European Union and China and the United States of America (USA) and China in space law degree education, course, teaching methodology, institute and practice and communication platform are provided in an attempt to review some issues which exist within the Chinese space law educational system and to seek a better choice for China’s space law education reform. Chinese space law education has achieved noticeable progress over the past two decades. However, it is still limited in comparison to its counterparts in Europe and Northern America. The range of the space law degree education programmes and space-law-related courses is comparatively limited. A gap remains between space law education and practice in China. Chinese space law classes are still dominated by the teacher-centred teaching methodology, although several universities have some new teaching practices. The establishment of seven space law-related research institutes plays an increasingly important role in Chinese space law education, space law and policy research and legal advisory services for the Chinese government and non-governmental sectors. However, these institutes still have a long way to go in comparison with their counterparts in Europe and Northern America. While China has established domestic research platforms for space law communication through international cooperation, it does not provide space law practice platforms for space law education. While international space law does not provide a direct legal foundation for space law education in China, Chinese educational laws can lay a profound legal foundation for Chinese space law education. To promote its national expertise and capacity in space law, based on the three-pillar model and the experiences of its counterparts in North America and Europe, China should adopt a systematic and sustainable regime for its space law education.     

大气探测激光雷达校飞样机研制与飞行验证

星载激光雷达是高精度测量全球温室气体和气溶胶垂直廓线的重要手段，大气环境监测卫星大气探测激光雷达(ACDL)在国际首次采用激光积分路径差分吸收技术测量全球CO2柱浓度，采用532 nm高光谱探测技术测量气溶胶和云的廓线。星载激光雷达载荷研制期间，同步研制一套主要功能一致的机载大气探测激光雷达校飞样机，并开展机载飞行试验，获取了大量飞行试验及其对比数据，提供了机载平台真实的数据源，对于优化ACDL激光雷达系统参数和研究星载数据反演算法至关重要。最后在机载飞行平台下，验证了优于1 ppm的CO2柱浓度测量精度和优于15%的气溶胶测量精度。未来利用该机载样机可以进一步开展星地对比验证。     

Hardware qualification for scientific ballooning missions

The European Stratospheric Balloon Observatory (ESBO) initiative aims at simplifying the access to stratospheric balloon missions. We plan to provide platforms and support with instrument design in order to support scientists. During the design process, the inevitable question of qualification for the harsh flight conditions arises. Unfortunately, there is no existing standard for qualification of stratospheric ballooning hardware. Thus, we developed a qualification procedure for use within ESBO and similar projects.In this paper, we present our analysis of the environmental conditions in the stratosphere. While conditions at typical balloon float altitudes are similar to the space environment, there are also some relevant differences. For example, the thermal environment is dominated by radiation and thermal conduction, but the remaining atmosphere still supports a certain amount of convection. The remaining atmospheric pressure in the stratosphere also leads to reduced arcing distances. Vibrational loads are far less than for space missions, but quasi-static or shock loads may occur. The criticality of radiation increases with mission duration.Based on the environmental conditions, we present the qualification procedures for ESBO, which are based on the European Cooperation for Space Standardization (ECSS) standards for space systems. Overtesting against too high requirements leads to overengineering, driving mission cost and mitigating the advantages of balloons over space missions. Therefore, we modified the ECSS standards to fit typical scientific ballooning missions over several days at altitudes up to 40 km. Furthermore, we analyzed design rules for space systems with regard to their relevance for scientific ballooning, including material and component selection. We present the experience from the hardware qualification process for the ESBO prototype STUDIO (Stratospheric UV Demonstrator of an Imaging Observatory). Even though boundary conditions are different for each individual mission, we aimed for a broader approach: We investigated more general requirements for scientific ballooning missions to support future flights.     

大气环境监测卫星星载激光雷达二氧化碳遥感反演方法及精度验证

目前卫星被动遥感二氧化碳存在空间覆盖不足、时空分辨率不够、地球两极和夜间缺少数据等问题，对二氧化碳的源汇研究带来很大的不确定度，同时也制约着利用卫星遥感温室气体探究全球变化。2022年4月我国发射了全球首颗搭载主动激光雷达探测二氧化碳的卫星-大气环境卫星。其上搭载了的气溶胶和碳探测激光雷达(ACDL)，利用1 572 nm的两束激光，可以反演干空气中加权平均的二氧化碳柱浓度。初步与香河站(全球碳柱总量观测网)站点比对的平均偏差为0.48 ppm，Sodankyla(全球碳柱总量观测网)站点的比对的平均偏差为0.8 ppm，精度超过被动遥感卫星。     

Study on excitation force characteristics in a coupled shaker-structure system considering structure modes coupling

The interaction between an elastic structure and electrodynamic shakers commonly exists in Ground Flutter Simulation Tests(GFST) with multi-point excitations, causing a considerable discrepancy between the practical excitation forces and desired ones. To investigate the excitation force characteristics on a cantilever beam excited by a voltage-sourced electrodynamic shaker,the coupled shaker-beam system is modeled to derive the excitation force formula using Hamilton’s principle and Galerkin’s a...