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Updated: May 25, 2025

11:34
Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
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大型主带小行星的形状,与水静平衡的偏差以及地质物理特性
J Vermersch1, N Rambaux1, B Sicardy1
1IMCCE, Observatoire de Paris, PSL Université, Sorbonne Université, Université Lille 1, CNRS UMR 8028, 77 Avenue Denfert-Rochereau, Paris 75014, France.
概括
大多数小行星接近球状形状,但很少有符合矮行星分类的水静平衡标准. 许多小行星的形状受到内部结构和环境破坏的影响,而不仅仅是重力.
科学领域:
- 行星科学 行星科学
- 小行星地质物理学
背景情况:
- 高角分辨率成像调查提供了精确的小行星形状模型.
- 了解小行星平衡数字对于分类小天体至关重要.
研究的目的:
- 确定42个小行星主要带的平衡值.
- 根据形状,定义矮行星和小行星之间的尺寸限制.
- 分析从水静电平衡的偏差.
主要方法:
- 使用SPHERE/ZIMPOL仪器进行成像.
- 应用球体波分析来塑造模型.
- 计算最小化标准来量化水静平衡偏差.
主要成果:
- 80%的小行星呈现球形形状.
- 只有九颗富含挥发物质的小行星与麦克劳林圆体相容.
- 30%显示差异化/化石形状;50%需要因环境损害而有失败标准.
结论:
- 小行星的形状受到超越水静平衡的因素的影响,包括内部特性和碰撞.
- 像地形和强度这样的地球物理参数在小行星之间有很大的不同.
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