旋转分解是小二进制小行星的起源
Kevin J Walsh1, Derek C Richardson, Patrick Michel
1UMR 6202 Cassiopée, University of Nice-Sophia Antipolis, CNRS, Observatoire de la Côte d'Azur, BP 4229, 06304 Nice Cedex 4, France. kwalsh@oca.eu
Nature
|July 11, 2008
概括
热YORP效应可以解释小小行星如何形成卫星. 这种机制导致废墟堆小行星旋转起来,流失质量,形成一个靠近轨道的二次天体.
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:
- 带有卫星的小行星在整个太阳系中被观测到,从近地小行星对到柯伊伯带对象.
- 小小行星二进制星系,在近地和内主带群体中很常见,具有快速旋转的初级星系和密切的圆形二次轨道.
- 大约15%的直径小于10公里的小行星拥有卫星,但这些双星的形成机制仍然不清楚.
研究的目的:
- 为了研究小小行星二进制星的形成机制.
- 解释不同动态群体中小行星二进制系统的共同特征.
主要方法:
- 使用热YORP效应建模"废墟堆"小行星的旋转.
- 分析来自临界旋转天体和卫星积聚条件的质量流失.
- 将模型生成的二进制属性与观察到的小行星系统进行比较.
主要成果:
- 热YORP效应提供了一个统一的机制,用于在近地和主带人口中形成小行星二进制星系.
- 从缓慢旋转的,长长的初级小行星中流出的质量在特定条件下积聚成卫星.
- 该模型成功地复制了小小行星二进制系统的观测特性,包括它们的轨道特征和1999 KW的例子.
结论:
- 热YORP效应是造成小小行星二进制星系的主要机制.
- 这种机制解释了小小行星周围卫星的流行和特征.
- 这些发现协调了在不同的动态环境中对小行星双星的观测.
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