The Inventory of Stardust Grains in the Solar Nebula - Implications from Isotopic and Petrologic Studies of Primitive Solar System Materials

太阳星云中星尘颗粒的清单——原始太阳系材料的同位素和岩石学研究的启示

• 批准号: 145226721
• 负责人: Privatdozent Dr. Peter Hoppe
• 金额: --
• 依托单位: Max-Planck-Institut für Chemie (Otto-Hahn-Institut)
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2010
• 资助国家: 德国
• 起止时间: 2009-12-31 至 2013-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/145226721?language=en
• 关键词: Inventory; Stardust; Grains; Solar; Nebula

Primitive meteorites, interplanetary dust particles, and samples from comet 81P/Wild 2 contain small quantities of refractory dust grains that are older than our Solar System and which formed in the winds of evolved stars or in the ejecta of stellar explosions. These presolar (stardust) grains can be identified on the basis of large isotopic anomalies with respect to average Solar System matter. Their abundances vary among different primitive Solar System materials, apparently reflecting processes of secondary alteration (e.g., aqueous alteration or thermal heating) and possibly also heterogeneities in the solar nebula. Here, we will continue to investigate the presolar grain inventories of CR clan chondrites, which are amongst the most primitive meteorites known, by NanoSIMS ion imaging. The matrix petrology in these meteorites will be studied in detail by optical microscopy and electron microprobe and compared with the presolar grain inventory to investigate the effects of thermal and aqueous alteration, genetic relationships and formation scenarios for CR clan chondrites, and to infer constraints on the presolar grain abundance in the solar nebula. We will also continue to study matter from comet Wild 2, returned by NASA’s STARDUST mission, in order to explore the currently not well determined presolar grain abundance in matter from this pristine Solar System body. These studies will be complemented by a search for and possible chemical and isotopic studies of residues in impact craters in Al foils from STARDUST’s interstellar dust collector.

原始的陨石，星际尘埃颗粒和来自彗星81p/野生2的样品包含少量的比我们太阳系古老的难治性粉尘晶粒，它们在进化的恒星的风中或在恒星爆炸的喷射中形成。相对于平均太阳系物质，可以基于大的同位素异常来识别这些前置（星尘）晶粒。它们的抽象在不同的​​原始太阳系材料之间有所不同，显然反映了次要改变的过程（例如，水性蚀变或热加热），以及太阳星云中可能的异质性。在这里，我们将继续研究Nanosims离子成像的CR氏族软骨的前粒晶粒库存。这些陨石中的基质岩石学将通过光学显微镜和电子显微探针进行详细研究，并与前谷物库存进行了比较，以研究热改变和水性变化的影响，CR氏族软骨的遗传关系和形成场景的影响，并推断出对近牛氏菌群的前粒晶粒含量的约束。我们还将继续从NASA的Stardust Mission返回的Comet Wild 2中研究事务，以探索目前从这个原始太阳系主体中尚未确定的前粒谷物丰度。这些研究将通过搜索和可能的化学和同位素研究来完成。