这是土星G环的来源
Matthew M Hedman1, Joseph A Burns, Matthew S Tiscareno
1Department of Astronomy, Cornell University, Ithaca, NY 14853, USA. mmhedman@astro.cornell.edu
Science (New York, N.Y.)
|August 4, 2007
概括
土星的G环很可能起源于一个被困在与月亮Mimas共振中的碎片弧. 这一弧既含有尘埃,也含有较大的物体,这表明环系的独特起源.
科学领域:
- 行星科学 行星科学
- 天文学 天文学
- 环形动力学 环形动力学
背景情况:
- 土星狭窄的G环的起源在行星科学中仍然是一个未解决的问题.
- 以前的观测主要在G环内发现了小颗尘埃粒.
研究的目的:
- 调查土星G环的来源和组成.
- 为了解释在G环内存在一个明亮的,局部的弧形.
主要方法:
- 来自卡西尼号航天器的数据分析,包括摄像头观测和能量粒子流量测量.
- 轨道动力学计算以确定环材料和土星卫星之间的共振相互作用.
主要成果:
- 在G环中发现了一个明亮的弧形,距离土星中心大约167,496公里.
- 这个弧被困在与月亮Mimas的7:6旋转异心共振中.
- 观测表明,这条弧既包括小的尘埃颗粒,又包括更大,厘米到米大小的物体,这意味着总质量相当大.
结论:
- G环的起源很可能与这种碎片弧有关,可能是由较大的物体的侵蚀形成的.
- 涉及这些较大的物体的碰撞可能会不断地使G环充满尘埃.
- 与Mimas的共振对于保持该弧的稳定性和结构至关重要,因此,G环.
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