Isotopic, elemental, and structural analysis of presolar matter

太阳前物质的同位素、元素和结构分析

• 批准号: 14638848
• 负责人: Privatdozent Dr. Thomas Stephan
• 金额: --
• 依托单位: Department of the Geophysical Sciences
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2006
• 资助国家: 德国
• 起止时间: 2005-12-31 至 2008-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/14638848?language=en
• 关键词: Isotopic; elemental; structural; analysis; presolar

Presolar grains, or grains originating prior to the formation of the Sun, have been found in primitive meteorites, interplanetary dust particles, and in the cometary samples collected by the NASA mission Stardust. They are identified by their highly anomalous isotopic composition, which is indicative of their condensation around final stage stars, which eject such material in giant explosions or during increased stellar winds. Modern analytical tools permit the investigation of individual presolar grains and their constituents, which reveal evidence of the processes occurring within stars. We intend to study in situ with TOF-SIMS, TEM, and NanoSIMS the chemistry and structure of presolar grains in the various types of primitive Solar System samples. Our analyses will focus on how presolar grains are incorporated into early Solar System materials and their survival to present time. In particular, samples from NASA's Stardust mission to comet Wild 2, the first extraterrestrial solid samples returned for laboratory analysis by a space mission since the lunar missions, are essential in this study. We will obtain the elemental, isotopic, and mineralogical composition of presolar grains in order to identify the stellar sources of the starting material of the Solar System, and to delineate the stellar, interstellar, and protoplanetary processes in which cometary grains may be involved.

太阳前颗粒，或起源于太阳形成之前的颗粒，已经在原始陨石、行星际尘埃颗粒和NASA使命星尘收集的彗星样本中发现。它们的同位素组成非常异常，这表明它们在最后阶段的恒星周围凝结，这些恒星在巨大的爆炸或增加的恒星风中喷出这些物质。现代分析工具允许研究单个太阳前颗粒及其成分，这揭示了恒星内部发生过程的证据。我们打算用TOF-SIMS，TEM和NanoSIMS原位研究各种类型原始太阳系样品中太阳前颗粒的化学和结构。我们的分析将集中在太阳前颗粒是如何被纳入早期太阳系材料和他们的生存到现在的时间。特别是，从美国宇航局的星尘使命到彗星野生2号的样本，第一个外星固体样品返回实验室分析的空间使命以来，月球任务，是必不可少的这项研究。我们将获得太阳前颗粒的元素、同位素和矿物学组成，以确定太阳系起始物质的恒星来源，并描绘可能涉及彗星颗粒的恒星、星际和原行星过程。