Micrometeoroid Mass Flux Influences on Space Weather and Middle Atmosphere Aeronomy Studied Using the Six NSF Radars and Modeling

使用六台 NSF 雷达和建模研究微流星体质量通量对空间天气和中层大气航空学的影响

• 批准号: 1202019
• 负责人: John Mathews
• 金额: $ 54万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-15 至 2016-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1202019&HistoricalAwards=false
• 关键词: Micrometeoroid; Mass; Flux; Influences; Space

The investigators will conduct observational and theoretical studies of meteoroid-related processes in the mesosphere and lower thermosphere (MLT). The study will utilize observations at the six NSF radars (and associated lidars), as a diversity of frequencies, viewing angles relative to the geomagnetic field, and latitudes/seasons is required to determine the whole earth meteoroid mass flux, explore the head/trail-echo scattering mechanisms, and to reveal details of the meteoroid interaction with the atmosphere including fragmentation, ablation, sputtering, and the resultant plasma physics and aeronomic effects. The complex role of the meteoroid mass flux to the Mesosphere & Lower-Thermosphere (MLT) on the aeronomy and electrodynamics of this region as represented by, e.g., sporadic-E, sporadic metal layers, and Polar Mesospheric Summer Echoes (PMSE), remains an illusive and even unrecognized component of space weather. Detailed understanding of the radio science of the radar head/trail-echo radar scattering processes is required to correctly interpret how the plasma surrounding the meteoroid--and that then forms the meteor trail--is generated and evolves, thus revealing important insights into sputtering, fragmentation, and terminal processes. Details of these processes remain a source of controversy. The investigators will also study how the meteoroid metals arrive in tidal ion, sporadic-E layers, noctilucent clouds, and PMSE. Modern high-power, large-aperture (HPLA) radar meteor observations have greatly stimulated the entire field of meteor physics and associated aeronomy. Observational and modeling/simulation studies of the radar meteor head/trail-echo scattering processes provide unique insight into meteoroid interaction with the atmosphere and also into the contribution of meteoric ions and "smoke" to the ionospheric D- and E-regions. The observations will provide details on how the meteoroid plasma trail evolves into geomagnetic field aligned plasma structures and will explore the surprising and instructive meteoroid flare generated plasma waves that produce non-thermal radar scattering. Together with radar observations, Rayleigh and metal lidar results provide a new dimension to meteoroid flux aeronomic studies. The meteoroid flux into the MLT is linked to solar system and local galactic processes. These are "systems of systems" space weather issues where meteoroid energy dissipation heating of the upper atmosphere is of the same order as Joule and particle heating of the auroral zones--an apparently unrecognized property of the meteoroid flux. This study will also lead to the development of new radar imaging techniques and help address issues such as the role of the meteoroid mass flux in many lower atmospheric processes such as cloud formation and stratospheric chemistry. Exploration of meteor-related electrodynamics and non-equilibrium plasma physics may stimulate other areas of research in, for example, the ionospheric heating community. This research will involve both graduate and undergraduate researchers, featuring discovery and learning to communicate knowledge concerning the meteoroid processes, related spaceweather and systems issues, and associated aeronomy.

调查人员将对中间层和低热层中与流星体有关的过程进行观测和理论研究。 该研究将利用六个NSF雷达的观测结果（和相关的激光雷达），因为需要多种频率、相对于地磁场的视角和纬度/季节来确定整个地球流星体质量通量，探索头部/尾部回波散射机制，并揭示流星体与大气相互作用的细节，包括碎裂、烧蚀、溅射，以及由此产生的等离子体物理和空气力学效应。流到中间层低热层（MLT）的流星体质量通量对该区域的高层大气学和电动力学的复杂作用，例如，零星的E，零星的金属层，和极地中层夏季回波（PMSE），仍然是一个虚幻的，甚至未被识别的空间天气的组成部分。 需要详细了解雷达头/尾回波雷达散射过程的无线电科学，才能正确解释流星体周围的等离子体（然后形成流星轨迹）是如何产生和演变的，从而揭示重要的见解溅射、碎片和终端过程。 这些过程的细节仍然是争议的根源。研究人员还将研究流星体金属如何到达潮汐离子，零星的E层，潮汐云和PMSE。 现代高功率、大孔径（HPLA）雷达流星观测极大地刺激了流星物理学和相关高空大气物理学的整个领域。对雷达流星头/尾回波散射过程的观测和建模/模拟研究提供了独特的见解，使人们了解流星体与大气的相互作用，以及流星体离子和“烟”对电离层D区和E区的贡献。这些观测将提供有关流星体等离子体尾迹如何演变成与地磁场对准的等离子体结构的细节，并将探索令人惊讶和有启发性的流星体耀斑产生的产生非热雷达散射的等离子体波。与雷达观测一起，Rayleigh和金属激光雷达结果为流星体通量空气动力学研究提供了新的维度。进入MLT的流星体流量与太阳系和本地星系过程有关。 这些都是“系统中的系统”空间天气问题，其中高层大气的流星体能量耗散加热与极光区的焦耳和粒子加热处于同一量级--流星体通量的一个明显未被认识到的属性。 这项研究还将导致开发新的雷达成像技术，并有助于解决流星体质量通量在云的形成和平流层化学等许多低层大气过程中的作用等问题。对流星相关电动力学和非平衡等离子体物理学的探索可能会刺激其他研究领域，例如电离层加热领域。 这项研究将涉及研究生和本科生研究人员，其特点是发现和学习有关流星体过程、相关空间天气和系统问题以及相关高层大气学的知识。