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特洛伊二进制小行星617 Patroclus的低密度为0.8 g cm(-3)
Franck Marchis1, Daniel Hestroffer, Pascal Descamps
1Department of Astronomy, University of California, 601 Campbell Hall, Berkeley, California 94720, USA. fmarchis@berkeley.edu
Nature
|February 3, 2006
概括
木星木马小行星617 Patroclus,一个二进制系统,有一个确定的轨道,揭示了它的组成部分以循环轨道移动. 这一发现表明小行星是多孔的或冰冷的,可能是在外太阳系形成的.
科学领域:
- 天文学和天体物理学.
- 太阳系探索太阳系探索
- 小行星研究研究.
背景情况:
- 木星木马是小行星共享木星的轨道在稳定的拉格朗日点 (L4和L5).
- 小行星617 Patroclus是唯一已知的二进制特洛伊木马小行星,其轨道动态以前未被描述.
研究的目的:
- 为了确定二进制小行星617 Patroclus的轨道特征.
- 根据617 Patroclus的轨道和热数据推断617 Patroclus组件的物理性质和起源.
主要方法:
- 观测天文学来追踪二进制元件的运动.
- 用热量测量来估计小行星组成部分的大小.
- 轨道力学计算以建模系统的动力学.
主要成果:
- 617 Patroclus 的两个组成部分以大致圆形的轨道绕着它们的共同质量中心运行,相隔680公里.
- 组件的密度非常低,为0.8 g cm−3. 这些组件的密度非常低.
- 低密度表明有显著的多孔性或富含水冰的组成.
结论:
- 617 Patroclus的轨道和物理特性表明它可能是在外太阳系形成的.
- 这种二元木马提供了对木星木马群中的小行星组成和形成的洞察.
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