A multiple-impact origin for the Moon
A multiple-impact origin for the Moon
复制标题
月球的多重撞击起源
DOI：
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
H. Perets
中科院分区：
文献类型：
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作者：
R. Rufu;O. Aharonson;H. Perets
月球起源于一次巨大撞击的假说可以解释地月系统的某些方面。然而，在不违反角动量约束的情况下，很难将巨型撞击模型与地球和月球的成分相似性相协调。此外，成功的巨型撞击情景需要非常具体的条件，这样它们发生的概率就很低。在这里，我们提出的数值模拟表明，月球可能是一系列各种较小的碰撞的产物。在这种情况下，每一次碰撞都会在原地球周围形成一个碎片盘，然后这些碎片盘聚集形成一个小卫星。小卫星潮汐式地向外移动，并可能合并形成月球。我们发现，在月球下的小卫星是一个共同的结果，预计在太阳系早期的原地球上的影响，并发现行星的旋转是有限的影响角动量流失。我们的结论是，假设有效的合并的小卫星，多个影响的情况下，可以解释形成的地月系统与其目前的属性。一个巨大的撞击被认为是形成月球的原因，但符合现有限制的情况是不可能的。现在的数值模拟表明，一系列更小、更常见的撞击可以解释地月系统。
The hypothesis of lunar origin by a single giant impact can explain some aspects of the Earth–Moon system. However, it is difficult to reconcile giant-impact models with the compositional similarity of the Earth and Moon without violating angular momentum constraints. Furthermore, successful giant-impact scenarios require very specific conditions such that they have a low probability of occurring. Here we present numerical simulations suggesting that the Moon could instead be the product of a succession of a variety of smaller collisions. In this scenario, each collision forms a debris disk around the proto-Earth that then accretes to form a moonlet. The moonlets tidally advance outward, and may coalesce to form the Moon. We find that sub-lunar moonlets are a common result of impacts expected onto the proto-Earth in the early Solar System and find that the planetary rotation is limited by impact angular momentum drain. We conclude that, assuming efficient merger of moonlets, a multiple-impact scenario can account for the formation of the Earth–Moon system with its present properties. A giant impact has been proposed as being responsible for forming the Moon, but scenarios that match existing constraints are improbable. Numerical modelling now suggests that instead a series of smaller and more common impacts can explain the Earth–Moon system.
影响因子：
64.8
作者：
Kruijer, Thomas S.;Kleine, Thorsten;Sprung, Peter
通讯作者：
Sprung, Peter
DOI：
10.1088/0004-637x/751/1/32
发表时间：
2012
期刊：
The Astrophysical Journal
影响因子：
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作者：
Stewart S
通讯作者：
Stewart S