We use a hybrid numerical approach to simulate the formation of the Moon from an impact-generated disk, consisting of a fluid model for the disk inside the Roche limit and an N-body code to describe accretion outside the Roche limit. As the inner disk spreads due to a thermally regulated viscosity, material is delivered across the Roche limit and accretes into moonlets that are added to the N-body simulation. Contrary to an accretion timescale of a few months obtained with prior pure N-body codes, here the final stage of the Moon's growth is controlled by the slow spreading of the inner disk, resulting in a total lunar accretion timescale of ~10^2 years. It has been proposed that the inner disk may compositionally equilibrate with the Earth through diffusive mixing, which offers a potential explanation for the identical oxygen isotope compositions of the Earth and Moon. However, the mass fraction of the final Moon that is derived from the inner disk is limited by resonant torques between the disk and exterior growing moons. For initial disks containing < 2.5 lunar masses (ML), we find that a final Moon with mass > 0.8ML contains < 60% material derived from the inner disk, with this material preferentially delivered to the Moon at the end of its accretion.
Global regolith thermophysical properties of the Moon from the Diviner Lunar Radiometer Experiment
我们使用月球勘测轨道飞行器（LRO）的红外数据占卜者月球辐射计实验全球地图的月球风化层细粉层的热物理特性。热导率从表面的7.4 $\times$ 10 $^{-4}$ W m $^{-1}$ K $^{-1}$变化到$\sim$ 1 m深度的3.4 $\times$ 10 $^{-3}$ W m $^{-1}$ K $^{-1}$，给定表面的密度值为1100 kg m $^{-3}$，到1 m深度的1800 kg m $^{-3}$。平均而言，这些配置文件的标度高度为$\sim$ 7厘米，对应于55 $\pm$ 2 J m $^{-2}$ K $^{-1}$ s $^{-1/2}$在273 K的热惯性，相关的日常活跃的近地表层，$\sim$ 4-7厘米。热导率和热容的温度依赖性导致赤道热惯性的$\sim$ 2 $\times$日变化。在全球范围内，风化层细粉是非常均匀的，这意味着快速均匀化的影响园艺这一层的时间尺度$<$ 1 Gyr。区域和局部尺度的变化显示出$<$ 1 Gyr old的突出撞击特征，包括哥白尼年龄撞击坑内部和喷出物的较高热惯性（$>$ 100 J m $^{-2}$ K $^{-1}$ s $^{-1/2}$），以及Bandfield等人（2014年）确定的月球冷点内的较低热惯性（$<$ 50 J m $^{-2}$ K $^{-1}$ s $^{-1/2}$）。…
Thick Lunar Crust Amplifies Deci-Hertz Gravitational-Wave Signal
Institute of Geology and Geophysics, Chinese Academy of Sciences（中国科学院地质与地球物理研究所）；Department of Astronomy, School of Physics, Peking University（北京大学物理学院天文学系）；Kavli Institute for Astronomy and Astrophysics, Peking University（北京大学科维理天文与天体物理研究所）
