相关实验视频
Updated: Aug 9, 2026

11:34
Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
近距离飞越253马蒂尔德:一个C类小行星的图像
1J. Veverka, P. Thomas, A. Harch, B. Clark, J. F. Bell III, B. Carcich, J. Joseph, Center for Radiophysics and Space Research, Cornell University, Ithaca, NY 14853, USA. C. Chapman and W. Merline, Southwest Research Institute, 1050 Walnut Str.
概括
接近地球的小行星约会 (NEAR) 太空船
科学领域:
- 行星科学 行星科学
- 小行星研究研究.
- 太空探索 太空探索
背景情况:
- 小行星253马蒂尔德是一颗大型,不规则的,满坑的近地小行星.
- 它的表面是黑暗的,它的白度类似于CM碳状地铁.
- 之前的研究缺乏关于其物理性质的详细数据.
研究的目的:
- 为了确定小行星253马蒂尔德的物理特性.
- 调查其内部结构和组成.
- 为了将马蒂尔德与其他碳状石小行星进行比较.
主要方法:
- 1997年6月27日,NEAR航天器在飞越期间的近距离成像.
- 对表面白度和颜色进行光度分析.
- 从成像数据确定体积.
- 使用近距离航天器的多普勒追踪进行质量估计.
主要成果:
- 小行星253马蒂尔德的尺寸约为66x48x46公里.
- 表面的白度很低,在0.035到0.050之间,没有检测到变化.
- 平均密度计算为1.3 +/- 0.2 g/cm3.
- 这种密度大约是CM混凝土密度的一半.
结论:
- 小行星253马蒂尔德具有高度多孔的内部结构.
- 它的低密度表明其组成不同于典型的CM碳酸.
- 这些发现为近地小行星的性质提供了关键的见解.
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