3D Modelling of Impacts into Planetary Atmospheres

[参考译文]撞击是塑造太阳系中物体的基本过程。虽然它们在行星和卫星的形成阶段最为重要，但它们今天仍在发生，可能对人类和地球上的其他生命造成严重后果。这个项目由加州大学圣克鲁斯分校的埃里克·阿斯普豪格博士领导，重点研究碰撞过程的一个重要方面：碰撞发生时，撞击体与行星（或卫星）大气的相互作用。研究小组将在先前模拟金星大气层撞击的工作基础上，对这一过程有更全面的了解。早期的工作表明，为了彻底限制撞击的物理性质，高分辨率的三维计算是必要的。这个项目的基本目标是回答以下问题：给定撞击的参数，到达地面形成陨石坑的质量和动量是多少？大气阻止撞击物体的能力如何？撞击体在大气中是如何分解的？利用三维流体动力学建模的结果，一个相对简单的大气渗透率模型将被开发出来，并由来自地球和金星的“地面真实”数据进行校准。这将有助于回答一些必然的问题：确定金星表面的年龄，确定中等大小的地球撞击物在哪里储存它们的能量，并预测泰坦表面的状态。＊＊＊

AST 0098707AsphaugImpacts are fundamental processes that have shaped the objects in the Solar System. While they were most important during the formation phase of the planets and satellites, they continue to occur today, with potentially severe consequences for humanity and other life on the Earth. This project, lead by Dr. Erik Asphaug at the University of California at Santa Cruz, focuses on an important aspect of the process: the interaction of an impacting body with a planetary (or satellite) atmosphere, as the collision takes place. The research team will build on previous work in simulating impacts into the Venusian atmosphere to develop a more complete understanding of the process. Earlier work demonstrated that high resolution three-dimensional calculations are necessary in order to thoroughly constrain the physics of impacts. The basic goals of this project are to answer the questions: Given the parameters of an impact, what are the mass and momentum that reach the ground to make a crater? How well do atmospheres stop impacting objects? How does an impactor break up in an atmosphere? Using the results of three-dimensional hydrodynamic modeling, a relatively simple model of atmospheric permeability will be developed, calibrated by "ground truth" data from the Earth and Venus. This will enable answering corollary questions: to determine the age of the surface of Venus, to determine where Earth impactors of moderate size deposit their energy, and to predict the state of the surface of Titan. ***