论文标题
地下岩浆海洋和化石图的地球系统的热轨道演变
The thermal-orbital evolution of the Earth-Moon system with a subsurface magma ocean and fossil figure
论文作者
论文摘要
已经提出了各种理论来解释月球当前的倾斜轨道。我们通过重建月球的热轨道历史来检验这些理论的生存能力。我们以过去的热轨道模型为基础，并结合了月球图的演变，包括化石图。月球岩浆海洋中的倾斜潮汐加热会产生迅速的倾斜度阻尼，使得早期倾向很难生存到当今。仅当早期月亮的固体体体比目前较小的耗散时，才能保留早期的倾斜度。如果拉普拉斯平面过渡是倾斜度的来源，则月亮必须缓慢退缩，这与先前关于弱消散的早期地球的发现是一致的。如果在月球形成之后，无碰撞的行星遇到最多140 Myr的行星激发了倾斜度，那么月球必须迅速迁移才能通过33 Earth Radii处的Cassini国家过渡，并达到有限的倾斜度阻尼时期。化石图很可能是在16个地球半径之前建立的，以匹配当今的2级重力场观测值。
Various theories have been proposed to explain the Moon's current inclined orbit. We test the viability of these theories by reconstructing the thermal-orbital history of the Moon. We build on past thermal-orbital models and incorporate the evolution of the lunar figure including a fossil figure component. Obliquity tidal heating in the lunar magma ocean would have produced rapid inclination damping, making it difficult for an early inclination to survive to the present-day. An early inclination is preserved only if the solid-body of the early Moon were less dissipative than at present. If instabilities at the Laplace plane transition were the source of the inclination, then the Moon had to recede slowly, which is consistent with previous findings of a weakly dissipative early Earth. If collisionless encounters with planetesimals up to 140 Myr after Moon formation excited the inclination, then the Moon had to migrate quickly to pass through the Cassini state transition at 33 Earth radii and reach a period of limited inclination damping. The fossil figure was likely established before 16 Earth radii to match the present-day degree-2 gravity field observations.
