3D Modelling of Impacts into Planetary Atmospheres

AsphaugImpact是塑造太阳系中天体的基本过程。虽然它们在行星和卫星的形成阶段是最重要的，但它们今天仍在发生，对人类和地球上的其他生命可能造成严重后果。该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，重点关注这一过程的一个重要方面：碰撞发生时，撞击天体与行星(或卫星)大气的相互作用。研究小组将在之前模拟影响金星大气的工作的基础上，对这一过程进行更全面的了解。早期的工作表明，为了彻底限制碰撞的物理学，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？大气在多大程度上阻止了物体的撞击？撞击器是如何在大气中分解的？利用三维流体力学模拟的结果，将开发一个相对简单的大气渗透率模型，并通过来自地球和金星的“地面真实”数据进行校准。这将使回答相应的问题成为可能：确定金星表面的年龄，确定中等大小的地球撞击体将能量储存在哪里，以及预测土卫六表面的状态。***

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. ***