撞击喷射作为孔德鲁尔的起源
Brandon C Johnson1, David A Minton2, H J Melosh2
1Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.
Nature
|January 17, 2015
概括
早期行星积聚过程中的冲击可以产生石中发现的孔德鲁. 这些发现表明石是行星形成的副产品,而不是剩余的构建块.
科学领域:
- 行星科学 行星科学
- 宇宙化学 宇宙化学
- 天体物理学 天体物理学
背景情况:
- 圆柱体是大多数石中发现的毫米尺度球体,先前是化的.
- 之前的模型表明,圆柱体形成发生在太阳星云中,但证据表明,固体丰富的环境,如撞击羽毛.
- 大多数chondrules的确切形成机制仍在争论中.
研究的目的:
- 为了调查原行星撞击是否可以产生观察到的丰富的chondrules.
- 为了确定撞击可以形成圆柱体的条件.
- 评估石撞击原点对石的撞击起源对石重要性的影响.
主要方法:
- 模拟原行星撞击来分析物质喷射和融化.
- 使用蒙特卡洛积累代码来建模构成圆柱体的撞击事件.
- 采用辐射转移模型来确定喷射滴的冷却速度.
主要成果:
- 冲击速度超过2.5公里/秒,可以在高速速度上化和弹出材料.
- 模拟显示,在积累的前500万年中,充足的孔德鲁生产.
- 喷射出来的融化液滴与体的尺寸和冷却速度相匹配,这是体的特征.
结论:
- 原行星撞击是大多数圆柱体的可行来源.
- 宏德鲁形成很可能发生在撞击产生的羽毛,而不仅仅是太阳星云.
- 石可能是行星形成的副产品,而不是原始的建筑材料.
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