石尘埃来自于大气中的一个大型石的分解
Andrew R Klekociuk1, Peter G Brown, Dee W Pack
1Space and Atmospheric Sciences, Australian Antarctic Division, Kingston, Tasmania 7050, Australia. andrew.klekociuk@aad.gov.au
Nature
|August 27, 2005
概括
大型石在地球大气层中产生显著的微米大小的尘埃,挑战了它们主要形成纳米大小的粒子的理论. 这一发现表明大气中石尘埃的主要来源.
科学领域:
- 太空尘埃的宇宙尘埃
- 大气科学 大气科学
- 地质化学 地质化学
背景情况:
- 在地球大气层中流星的消灭消耗了它们的大多数质量.
- 理论模型预测废弃物质回收到纳米尺寸的粒子 (流星烟雾).
- 缺乏直接测量石烟雾的方法.
研究的目的:
- 为了研究由一颗大型流星体的消去而产生的颗粒的尺寸分布.
- 将观测数据与对流星烟雾形成的理论预测进行比较.
- 为了确定地球大气中微米大小的石尘埃的主要来源.
主要方法:
- 对大气气溶组成的分析,大气溶分解后的大型石.
- 在残留大气气溶中的颗粒大小的表征.
- 观察到的粒子大小与理论模型的比较. 剥离和凝结.
主要成果:
- 剩余大气气溶的主要贡献者是微米大小的粒子,而不是纳米大小的粒子.
- 这一观察与目前普遍存在的有效转化为亚微米颗粒的理论相矛盾.
- 解体事件提供了直接证据,表明石消灭过程中存在粒子形成.
结论:
- 大型石可能是微米尺寸的石尘埃的更重要的来源,而不是以前的假设.
- 这项研究挑战了现有的流星废弃和粒子形成模型.
- 需要进一步的研究来证实大型石中微米大小的粒子形成的普遍性.
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