Bombardment history of the planets

行星轰炸历史

• 批准号: 0806828
• 负责人: Renu Malhotra
• 金额: $ 29.8万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-08-15 至 2012-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0806828&HistoricalAwards=false
• 关键词: Bombardment; history; planets

AST-0806828MalhotraIt is becoming increasingly clear that the planets and the planetesimals (the asteroids and Kuiper belt objects) in the solar system have co-evolved, such that the planets migrate and the planetesimal belts are depleted, while the bombardment rate on the planets evolves. This project will detail one crucial phase in this evolution, associated with the late heavy bombardment (LHB), some 3.9 billion years ago. Building on earlier evidence for the source and the mechanism of this event, this investigation will assess the number, sizes, and changing impact rates of the LHB and post-LHB impactors. Rigorous analysis and numerical modeling combined will identify the dominant and less dominant sources of the LHB and post-LHB impactors, and provide upper and lower limits on the duration of the LHB, its intensity on the Earth, Moon and other terrestrial planets, and the magnitude of depletion of the main asteroid belt.This research helps to understand the dynamical history of the planets and minor bodies of the solar system, especially the bombardment history of planet Earth, the crater-based geochronology of Mars and Mercury, and the history of the main asteroid belt. It adds impetus to renewed study of the Moon, and is also of interest to extra-solar planetary system studies. Knowledge gained during the study will be integrated into Dr Malhotra's natural sciences class, and meteorite bombardment and the history of early Earth have broad public and community interest.

AST-0806828 Malhotra越来越清楚的是，太阳系中的行星和微行星（小行星和柯伊伯带天体）共同进化，使得行星迁移，微行星带耗尽，而对行星的轰击率也在演变。 该项目将详细介绍这一演变中的一个关键阶段，与大约39亿年前的晚期重轰炸（LHB）有关。 在此事件的来源和机制的早期证据的基础上，本次调查将评估LHB和LHB后撞击物的数量、大小和不断变化的撞击率。 结合严格的分析和数值模拟，将确定LHB和LHB后撞击物的主导和次要来源，并提供LHB持续时间的上限和下限，其在地球，月球和其他类地行星上的强度，以及主小行星带的消耗量。这项研究有助于了解太阳系行星和小天体的动力学历史，特别是行星地球的撞击历史，火星和水星的陨石坑地质年代学，以及主小行星带的历史。 它增加了对月球的新研究的动力，也对太阳系外行星系统的研究感兴趣。 在研究过程中获得的知识将被整合到Malhotra博士的自然科学课程中，陨石轰击和早期地球的历史具有广泛的公众和社区利益。