Asteroid Risk Assessment: A Probabilistic Approach
Asteroid Risk Assessment: A Probabilistic Approach
复制标题
小行星风险评估：概率方法
作者：
J. Reinhardt;X. Chen;Wenhao Liu;P. Manchev;M. Paté
在2013年车里雅宾斯克事件之后，小行星带来的风险重新引起了科学界和决策界的兴趣。它提醒世界，近地天体（NEO）的影响虽然罕见，但有可能对城市和人口造成巨大损害。已经提出了风险的点估计（例如平均伤亡人数），但由于小行星撞击的低概率，高后果的性质，这些平均值提供的可操作信息有限。虽然还需要做更多的工作来进一步完善其输入分布（例如，近地天体直径），本文提出的概率模型可以对近地天体撞击的风险进行更全面的评价，因为其结果是涵盖潜在伤亡范围的分布。这一模型以模块化模拟为基础，利用概率性投入估计概率风险度量，包括小行星罕见撞击的概率风险度量。这一分析的说明性结果是一个为期100年。作为此次演示的一部分，我们评估了民防措施在减轻人员伤亡风险方面的有效性。我们发现它们可能是有益的，但不是万能的。我们还计算了全球影响（“灾难”）的可能性，但不是后果。我们的结论是，仍然需要对近地天体进行观测，并分析旨在偏转或摧毁威胁地球的小行星的空间飞行任务的可行性和降低风险的有效性。
Following the 2013 Chelyabinsk event, the risks posed by asteroids attracted renewed interest, from both the scientific and policy‐making communities. It reminded the world that impacts from near‐Earth objects (NEOs), while rare, have the potential to cause great damage to cities and populations. Point estimates of the risk (such as mean numbers of casualties) have been proposed, but because of the low‐probability, high‐consequence nature of asteroid impacts, these averages provide limited actionable information. While more work is needed to further refine its input distributions (e.g., NEO diameters), the probabilistic model presented in this article allows a more complete evaluation of the risk of NEO impacts because the results are distributions that cover the range of potential casualties. This model is based on a modularized simulation that uses probabilistic inputs to estimate probabilistic risk metrics, including those of rare asteroid impacts. Illustrative results of this analysis are presented for a period of 100 years. As part of this demonstration, we assess the effectiveness of civil defense measures in mitigating the risk of human casualties. We find that they are likely to be beneficial but not a panacea. We also compute the probability—but not the consequences—of an impact with global effects (“cataclysm”). We conclude that there is a continued need for NEO observation, and for analyses of the feasibility and risk‐reduction effectiveness of space missions designed to deflect or destroy asteroids that threaten the Earth.