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在切利亚宾斯克上空发生了500千的空气爆炸,小撞击器的危险性增加
P G Brown1, J D Assink, L Astiz
11] Department of Physics and Astronomy, University of Western Ontario, London, Ontario N6A 3K7, Canada [2] Centre for Planetary Science and Exploration, University of Western Ontario, London, Ontario N6A 5B7, Canada.
Nature
|November 8, 2013
概括
来自较小小行星的空气爆炸带来了重大撞击风险. 对切利亚宾斯克事件的分析表明,目前的损害模型高估了爆炸效应,这表明10-50米小行星的风险更大.
科学领域:
- 行星科学 行星科学
- 天体物理学 天体物理学
- 影响危险评估 影响危险评估
背景情况:
- 大多数大型近地小行星都已被目录,但较小的物体具有显著的,低估的撞击风险.
- 来自石的空气爆发,而不是地面撞击,是超过一定尺寸值的物体的主要损伤机制.
- 以前对气爆的损害估计可能是不准确的,因为它依赖于核武器的影响.
研究的目的:
- 分析2013年切利亚宾斯克小行星空爆造成的损害,并重新评估撞击风险评估模型.
- 为了比较观察到的空气爆破损害与既定技术的预测.
- 为了调查全球空气爆发事件并评估10-50米大小范围内的近地小行星的数量.
主要方法:
- 分析观测数据和切利亚宾斯克小行星空气爆发的损害报告 (大约. 19米直径,相当于500千的TNT).
- 观察到的损害与来自核武器影响和广泛引用的空气爆破损害技术的估计值进行比较.
- 全球对具有1千或更多能量的历史空气爆发事件的调查.
主要成果:
- 切利亚宾斯克空气爆炸的损害没有被标准的损害估计技术准确地复制,这些技术往往会高估爆炸效应.
- 基于核武器效应的数学模型对接近值大小的物体显著高估了空爆爆炸损害.
- 全球调查表明,直径为10-50米的撞击器的数量可能比之前估计的数量高出一个数量级.
结论:
- 目前用于估计空气爆炸损害的方法,特别是那些使用核武器类比的方法,可能会高估较小小行星带来的风险.
- 接近地球的小行星群体在10-50米大小范围似乎是不平衡的,可能比以前认为的要大得多.
- 剩余撞击风险的更大一部分现在归因于这些较小,更多的近地小行星.
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