小行星带被原始的跨海王星物体污染
Harold F Levison1, William F Bottke, Matthieu Gounelle
1[1] Southwest Research Institute, 1050 Walnut Street, Suite 300, [2] Center for Lunar Origin & Evolution, NASA Lunar Science Institute, Boulder, Colorado 80302, USA.
Nature
|July 17, 2009
概括
巨行星迁移将原始物体插入小行星带,解释了其多样化的组成. 这些被捕获的物体是原始微型石的主要来源.
科学领域:
- 行星科学 行星科学
- 天文学 天文学
- 天体物理学 天体物理学
背景情况:
- 主要的小行星带展示了各种各样的物体,从冰岩到岩石.
- 目前的模型表明小行星是在化学变化的原始磁盘内现场形成的.
研究的目的:
- 为了调查小行星带多样性的起源.
- 为了测试巨行星轨道动态对小行星组成的影响.
主要方法:
- 使用尼斯模型模拟了巨行星轨道的动态演变.
- 追踪了跨海王星物体的插入到外层小行星带的过程.
主要成果:
- 尼斯模型的巨行星迁移将原始的跨海王星物体插入到外层小行星带.
- 这解释了观察到的多样性,而不需要原行星盘的内在组成变化.
- 被捕获的有机丰富的物体对微流星群体做出了重大贡献,解释了它们原始和同位素上不同的性质.
结论:
- 小行星带的多样性受到外部物质输送的重大影响.
- 巨行星的动态在塑造内部太阳系天体的组成方面发挥着至关重要的作用.
- 原始石的起源与捕获的跨海王星物体有关.
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