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Scattering And Absorption of Light in Planetary Regoliths
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来自小行星带不稳定的延伸的阿基亚严重轰炸
William F Bottke1, David Vokrouhlický, David Minton
1Southwest Research Institute and NASA Lunar Science Institute, 1050 Walnut Street, Suite 300, Boulder, Colorado 80302, USA. bottke@boulder.swri.edu
Nature
|April 27, 2012
概括
晚期重型轰炸 (LHB) 时间比以前认为的要晚得多,撞击物源自E带. 这个地区 这个地区 这个地区
科学领域:
- 行星科学 行星科学
- 天文学 天文学
- 冲击石坑的形成
背景情况:
- 晚期重型轰炸 (LHB) 传统上被认为在37-38亿年前结束.
- 证据表明,LHB大小的地球撞击,以撞击球状床的形式,发生得更晚,延伸到早期的新生代.
研究的目的:
- 为了调查晚期重型轰炸的延长时间.
- 为了确定负责月球盆地和陆地撞击球状床的后期撞击物的来源.
主要方法:
- 对地球上的撞击球状床和月球石坑记录的分析.
- 模拟小行星带动力学和巨行星迁移.
- 从观测到的匈牙利小行星进行缩放,以估计撞击器流动.
主要成果:
- LHB持续时间远远长于先前的假设,大多数晚期冲击因素来自E带.
- 在37亿至41亿年前,E带射弹形成了大约10个月球盆地.
- 这些撞击还在17亿至37亿年前创造了许多陆地盆地和奇克苏鲁布大小的石坑.
结论:
- 由于巨行星迁移而破坏稳定的E带是后期撞击的重要来源.
- 由E带物体驱动的扩展LHB解释了观测到的撞击球状床和月球石坑率.
- 这一修订后的理解重新塑造了我们对太阳系早期轰炸历史的看法.
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