彗星和星际尘埃分析仪在81P/Wild 2彗星上
J Kissel1, F R Krueger, J Silén
1Max-Planck-Institut fur Aeronomie, Max-Planck-Strasse 2, D-37191 Katlenburg-Lindau, Germany.
Science (New York, N.Y.)
|June 19, 2004
概括
对彗星和星际尘埃的分析揭示了两者中的有机物质,包括子衍生物. 彗星尘埃失去气和氧气,变得富含气,而星际尘埃保留了这些元素.
科学领域:
- 太空化学 太空化学
- 天体生物学 天体生物学
- 行星科学 行星科学
背景情况:
- 星尘任务使用彗星和星际尘埃分析仪 (CIDA) 分析了彗星和星际尘埃.
- 以前的研究表明,有机分子可能存在于外星尘埃中.
- 了解尘埃组成是了解生命起源和行星形成的关键.
研究的目的:
- 分析星际和彗星尘埃颗粒的有机成分.
- 为了比较不同来源的尘埃的分子构成.
- 研究有机物质从星际空间到彗星的化学演变.
主要方法:
- 利用彗星和星际尘埃分析仪 (CIDA) 仪器,一个飞行时间质谱仪.
- 分析了来自45个被认为是星际尘埃粒子和来自81P/Wild 2彗星的29个粒子的离子光谱.
- 已识别的有机成分及其元素组成.
主要成果:
- 在星际尘埃颗粒的有机成分中发现了子衍生物.
- 证实了彗星尘埃中有机物质的普遍存在.
- 与星际尘埃相比,观测到彗星尘埃中和氧的耗尽,这些元素可能以气相 (水,一氧化碳) 的形式存在.
- 发现彗星尘埃中含有丰富的含物种.
- 没有检测到任何氨基酸,但在一个彗星尘埃谱中发现了硫离子.
结论:
- 彗星和星际尘埃共享有机成分,但经历了重要的化学加工.
- 从星际到彗星环境的过渡导致有机物质中失去和氧气.
- 和硫物种在彗星的有机化学中似乎很重要.
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