Dynamic Model of the Dust Cloud Around the Moon

月球周围尘埃云的动力学模型

• 批准号: 410413592
• 负责人: Privatdozent Dr.-Ing. Ralf Srama
• 金额: --
• 依托单位: Institut für Raumfahrtsysteme (IRS)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/410413592?language=en
• 关键词: Dynamic; Model; Dust; Cloud; Around

The data gathered by the LDEX detector onboard NASA’s LADEE mission shows that there is a permanent, asymmetric dust cloud around the Moon. The density of the dust grains in the cloud varies with annual meteoroid showers. Micron sized secondary ejecta particles generated by these meteoroid showers and interplanetary dust are considered as the main source of the lunar dust cloud. Our ultimate goal is the development of a dynamic model for the lunar dust cloud, and in this project we will focus on the main input of this model: distributions of micron sized ejecta grains with high speeds. For this, micron sized particles will be accelerated by the electrostatic dust accelerator located at IRS, the University of Stuttgart, and millimeter sized particles will be fired by a light gas gun operated by the Chinese partner, the Harbin Institute of Technology (HIT).The accelerated projectiles will cover the size range of 0.1 µm - 10 mm with speeds varying from 500 m/s to 50 km/s, to simulate the properties of meteoroid shower particles and interplanetary dust particles impacting on the lunar surface. The incident angles will vary from 15° to 90°. A PVDF detector array and an aerogel collector array will be designed to be able to monitor the mass, speed and angular distributions of ejecta grains created by the millimeter sized projectiles. The ejecta generation due to micron sized projectiles can be investigated with a multi-anode detector system and a delay line detector system. The target will be CSA-1 lunar regolith simulant, which was developed by the Chinese partner. The primary impactor flux onto the surface of the moon is determined using the latest models describing the meteoroid environment at the moon. These models are called IMEX and IMEM2 and were developed by the german partner. The models provide the flux, mass, velocity and angular distributions of the impacting grains. The experiments performed in this project characterize the secondary ejecta generated by the impacts. The ejecta dynamics is then modelled in order to fit the LDEX observations of the lunar dust cloud.Both parties have a lot of experience on space environments and hypervelocity impact research. All experimental tests and simulation studies are planned to be carried out using in-house acceleration facilities operated by the parties after 2019 allowing them to plan and perform the measurement campaigns in a time and cost efficient manner. The two parties have a long history in cooperation due to an early exchange of personnel (Dr. Li). Dr. Ing Ralf Srama is a foreign expert working at HIT with funds from the Chinese ‘111 Plan’ project, and he is the project leader of the development of a 3.5 MV dust accelerator located at HIT. The new development of a space environment model will allow German and Chinese space scientists to be in a world-wide leading position to explore new areas of astronomy and planetary science.

美国宇航局LADEE使命上的LDEX探测器收集的数据显示，月球周围有一个永久的、不对称的尘埃云。云中尘埃颗粒的密度随着每年的流星体阵雨而变化。由这些流星体簇射和行星际尘埃产生的微米级二次喷出物粒子被认为是月球尘埃云的主要来源。我们的最终目标是开发一个月球尘埃云的动力学模型，在这个项目中，我们将专注于这个模型的主要输入：微米大小的高速喷出物颗粒的分布。为此，微米级颗粒将由位于斯图加特大学IRS的静电尘埃加速器加速，毫米级颗粒将由中国合作伙伴哈尔滨工业大学（HIT）操作的轻气枪发射。加速的弹丸将覆盖0.1 µm - 10 mm的尺寸范围，速度从500 m/s到50 km/s不等。模拟流星体簇射粒子和行星际尘埃粒子撞击月球表面的特性。入射角将在15°至90°之间变化。将设计一个PVDF探测器阵列和一个气凝胶收集器阵列，以便能够监测毫米大小的射弹产生的喷出物颗粒的质量、速度和角分布。利用多阳极探测器系统和延迟线探测器系统可以研究微米级弹丸的喷射物生成。目标将是由中国合作伙伴开发的CSA-1月壤模拟物。利用描述月球流星体环境的最新模型来确定月球表面上的主要撞击物通量。这些型号被称为IMEX和IMEM 2，由德国合作伙伴开发。该模型提供了撞击颗粒的通量、质量、速度和角分布。该项目进行的实验描述了撞击产生的二次喷出物的特征。双方在空间环境和超高速撞击研究方面都有丰富的经验。所有实验测试和模拟研究计划在2019年后使用双方运营的内部加速设施进行，使他们能够以时间和成本效益的方式规划和执行测量活动。双方有着悠久的合作历史，因为早期的人员交流（李博士）。Ing Ralf Srama博士是在中国“111计划”项目资助下在哈工大工作的外国专家，他是哈工大3.5MV尘埃加速器开发的项目负责人。空间环境模型的新发展将使德国和中国的空间科学家处于世界领先地位，探索天文学和行星科学的新领域。