Asteroids and comets have the potential to impact Earth and cause damage at the local to global scale. Deflection or disruption of a potentially hazardous object could prevent future Earth impacts, but due to our limited ability to perform experiments directly on asteroids, our understanding of the process relies upon large‐scale hydrodynamic simulations. Related simulations must be vetted through code validation by benchmarking against relevant laboratory‐scale, hypervelocity‐impact experiments. To this end, we compare simulation results from Spheral, an adaptive smoothed particle hydrodynamics code, to the fragment‐mass and velocity data from the 1991 two‐stage light gas‐gun impact experiment on a basalt sphere target, conducted at Kyoto University by Nakamura and Fujiwara. We find that the simulations are sensitive to the selected strain models, strength models, and material parameters. We find that, by using appropriate choices for these models in conjunction with well‐constrained material parameters, the simulations closely resemble with the experimental results. Numerical codes implementing these model and parameter selections may provide new insight into the formation of asteroid families (Michel et al., 2015, https://doi.org/10.2458/azu_uapress_9780816532131‐ch018) and predictions of deflection for the Double Asteroid Redirection mission (Stickle et al., 2017, https://doi.org/10.1016/j.proeng.2017.09.763). Plain Language Summary Asteroid and comet impacts into Earth are a low‐probability but high‐consequence risk. Given that the risk exists, we prepare ahead of time by researching ways to stop a potentially hazardous object from hitting our planet. Conducting experiments in space on actual asteroids or comets to practice mitigation tactics is possible but limited. In the meantime, the planetary defense community uses codes to simulate different ways of stopping these potentially dangerous objects. But this begs the question, how do we know our codes are correct? In an effort to gain confidence in our codes, this work compares our simulation results to data from a well‐known laboratory‐scale experiment to assess the accuracy of our models. We find that our code can produce results that closely resemble the experimental findings, giving assurance to the planetary defense community that our code can correctly simulate asteroid or comet mitigation.
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机译：小行星和彗星有可能影响地球并导致当地到全球规模的损坏。偏转或潜在危险物体的破坏可以防止未来的地球影响，但由于我们在小行星上直接进行实验的能力有限，我们对该过程的理解依赖于大规模的流体动力模拟。相关模拟必须通过对相关实验室规模，超细性 - 影响实验进行基准测试来审核代码验证。为此，我们将仿真结果与马托斯大学在Nakamura进行的玄武岩大学进行的1991年两级轻型气枪冲击试验中的仿真结果，自适应平滑粒子流体动力学码。由Nakamura在京都大学进行的玄武岩球体目标中的碎片质量和速度数据和富士瓦拉。我们发现模拟对所选的应变模型，强度模型和材料参数敏感。 We find that, by using appropriate choices for these models in conjunction with well‐constrained material parameters, the simulations closely resemble with the experimental results.实现这些模型和参数选择的数值代码可以为小行星系列的形成提供新的洞察力（Michel等，2015，Https://Doi.org/10.2458/Azu_uapress_9780816532131-CH018）以及双张小笛重定向使命的偏转预测（Stickle等，2017年，https://doi.org/10.1016/j.proeng.2017.09.763）。普通语言摘要小行星和彗星撞击到地球是一种低概率，但风险很高。鉴于风险存在，我们提前通过研究阻止潜在危险物体来击中我们的星球的方法来准备。在实际小行星或彗星上进行实践缓解策略的空间进行实验是有限的。与此同时，行星防御社区使用代码来模拟停止这些潜在危险物体的不同方式。但这引出了问题，我们如何知道我们的代码是正确的？为了在我们的代码中获得信心，这项工作将我们的模拟结果与来自知名实验室规模实验的数据进行了比较，以评估模型的准确性。我们发现我们的代码可以产生与实验结果非常相似的结果，为行星防御社区提供保证，我们的代码可以正确模拟小行星或彗星缓解。
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