Collaborative Research: Arecibo Radar Studies of Zodiacal and Interstellar Dust in the Solar System.

AST 0205848数学博士宾夕法尼亚州立大学的John Mathews将与纽约州立大学Geneseo的David Meisel博士合作，基于在阿雷西博天文台进行的雷达微流星观测，对太阳系中的小粒子进行为期3年的观测和分析/建模研究。关于大约0.2-100微米大小的行星际尘埃粒子(IDP)的分布、来源和引力、电动力学演化的知识，对于行星科学以及--由于太阳系外和星际粒子也存在--对于当地的银河系科学来说是至关重要的。阿雷西博天文台的超高频雷达已被证明是唯一适合于地面微流星观测的设备，可以产生大量行星际和双曲尘埃粒子的速度、减速和辐射信息--从而产生轨道。观测结果现在从1997年一直延续到现在，一种稳步发展的技术现在产生了瞬时精度低至10米/秒的流星体多普勒速度(迄今流星体速度超过10-90公里/秒)。再加上基于经典的大气层内流星动力学的分类机制，可以清楚地将束下粒子与那些具有显著跨束速度分量的流星体区分开来。这项新的努力将这些研究扩展到太阳系内IDP分布/演化的细节，并考虑了星际粒子通量对太阳系的作用以及由该通量照亮的局部银河系过程/特征。由该奖项资助的新的观测/分析/建模研究将继续提供对IdP的常规采样，包括预期的跨地球小行星轨道粒子、星际粒子(ISP)、木星扰动和/或派生粒子，以及由太阳系内部辐射压力抛出的低质量b粒子。随着ISPS数据库的增长，这些研究人员将继续对最大的星际粒子的流量和起源进行理论/模型研究。到目前为止，它们可以解释所有的AO ISP都是产生Geminga脉冲星的同一颗超新星的产物。这项工作已经并将继续涉及来自纽约州立大学杰内索分校、宾夕法尼亚州立大学和其他机构的本科生和宾夕法尼亚州立大学的研究生以及阿雷西博天文台和其他组织的工作人员。这些努力的结果出现在Geneseo和宾夕法尼亚州立大学的几门课程中，包括电磁学、天体物理学和等离子体。

AST 0205848MathewsDr. John Mathews, at Penn State University, in collaboration with Dr. David Meisel, at State University of New York at Geneseo, will conduct a 3-year observational and analysis/modeling study of small particles in the Solar System based on radar micrometeor observations performed at the Arecibo Observatory. Knowledge of the distribution, sources, and gravitational, electrodynamical evolution of interplanetary dust particles (IDPs) in the ~0.2-100 micron size range is critical to the planetary sciences and-as extrasolar and interstellar particles are also present-to local galactic science. The Arecibo Observatory (AO) UHF radar has proven to be uniquely suited for ground-based micrometeor observations that yield velocity, deceleration, and radiant information-and thus orbits-of large numbers of interplanetary and hyperbolic dust particles. Observational results now extend from 1997 through the present with a steadily evolving technique that now yields meteoroid Doppler speeds with instantaneous accuracies of as small as 10 m/sec (with meteoroid speeds ranging over 10-90 km/sec thus far). This combined with a sorting mechanism based on classical, in-atmosphere meteoroid dynamics, clearly distinguishes down-the-beam particles from those meteoroids with a significant across-the-beam velocity component. The new effort extends these studies to details of IDP distribution/evolution in the solar system and considers the role of the interstellar particle flux to the solar system as well as local galactic processes/features illuminated by this flux.The new observational/analysis/modeling study funded with this award will continue providing routine sampling of IDPs including the expected earth-crossing asteroidal-orbit particles, interstellar particles (ISPs), Jovian perturbed and/or derived particles, and low-mass b particles ejected by radiation pressure from the inner solar system. As the database of ISPs grows, these researchers will continue theoretical/modeling studies of the flux and origins of the largest of the interstellar particles. Thus far they can account for all AO ISPs as being products of the same supernova thatproduced the Geminga pulsar. This effort has involved and will continue to involve undergraduates from SUNY-Geneseo, Penn State, and other institutions and graduate students from Penn State as well as the staff of Arecibo Observatory and other organizations. Results from these efforts appear in several courses including electromagnetics, astrophysics, and plasmas at both Geneseo and Penn State.***