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Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
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在由岩石孔隙性控制的小行星上生产细规律石
S Cambioni1,2, M Delbo3, G Poggiali4
1Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ, USA. saveriocambioni@email.arizona.edu.
Nature
|October 7, 2021
概括
在Bennu和Ryugu等多孔碳化小行星上,雷戈石的覆盖很罕见,因为它们的岩石压缩而不是碎片化. 这些地形可能更常见于较少多孔的岩石小行星上.
科学领域:
- 星球科学
- 小行星表面过程
- 雷戈利特物理
背景情况:
- 太空飞船的任务已经观察到石质小行星上未结合的 regolith.
- 望远镜数据表明碳化小行星上的规流石 (例如,贝努,瑞古).
- 观察到的碎片化过程与贝努和瑞古缺乏广泛的规石形成鲜明对比.
研究的目的:
- 探究碳化小行星表面显然缺少大量规流石的原因.
- 确定小行星Bennu上的岩石多孔性和亚厘米颗粒数量之间的关系.
- 在不同类型的小行星上推断出规律层的普遍性.
主要方法:
- 分析来自小行星Bennu的航天器任务数据.
- 当地亚厘米颗粒数量与岩石多孔性之间的相关性分析.
- 与岩石碎片和热裂的实验室实验进行比较.
主要成果:
- 在Bennu上发现了亚厘米颗粒数量与岩石多孔性之间的反向相关性.
- 贝努的多孔岩石被撞击压缩而不是碎片化.
- 与较密的岩石相比,热裂变的速度较慢.
结论:
- 在高度多孔的小行星表面上,未结合的亚厘米颗粒的积累受到阻碍.
- 由于岩石的多孔性,在碳化小行星上可能不常见.
- 预计在较不多孔的岩石小行星上,雷戈石地形很常见.
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