arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1609.07474astro-ph.EP
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地月系统全球潮汐耗散的标度

Scaling in global tidal dissipation of the Earth-Moon system

Maurice H. P. M. van Putten

摘要:

月球以$v=3.8$ cm/年$^{-1}$的速度,通过与地球海洋的潮汐相互作用,在一个特征时间$r/v=10^{10}$ Gyr内迁移到$r_{\leftmoon}\simeq3.8\times10^{10}$ cm。我们得出的全球耗散,涵盖了整个历史,在过去的4.52 Gyr的缩放。过去在相对较短的潮汐周期的非共振潮汐相互作用揭示了需要缩放{振幅}。本文用阻尼$ε= h F/(2Q_0)$模拟宽谱海浪中复杂的时空动力学和耗散的全局特性,其中$h$是潮波振幅,$F$是潮频率,$Q_0$是当前时刻的$Q$因子。它满足$Q_0\simeq 14$的迁移时间和月球年龄的一致性与观测的近共振状态今天。它显示了月球从接近罗氏极限的不稳定近同步轨道(可能位于原月盘中)的惊人快速驱逐。地球从最初的$\sim30\%$分裂的月球快速旋转下来,有利于早期形成全球气候。我们的理论表明,卫星可能对潜在的宜居系外行星同样有利。

英文摘要:

The Moon migrated to $r_{\leftmoon}\simeq3.8\times10^{10}$ cm over a characteristic time $r/v=10^{10}$ Gyr by tidal interaction with the Earth's oceans at a present velocity of $v=3.8$ cm yr$^{-1}$. We derive scaling of global dissipation that covers the entire history over the past 4.52 Gyr. Off-resonance tidal interactions at relatively short tidal periods in the past reveal the need for scaling {with amplitude}. The global properties of the complex spatio-temporal dynamics and dissipation in broad spectrum ocean waves is modeled by damping $ε= h F/(2Q_0)$, where $h$ is the tidal wave amplitude, $F$ is the tidal frequency, and $Q_0$ is the $Q$-factor at the present time. It satisfies $Q_0\simeq 14$ for consistency of migration time and age of the Moon consistent with observations for a near-resonance state today. It shows a startingly fast eviction of the Moon from an unstable near-synchronous orbit close to the Roche limit, probably in a protolunar disk. Rapid spin down of the Earth from an intial $\sim30\%$ of break-up by the Moon favored early formation of a clement global climate. Our theory suggests moons may be similarly advantageous to potentially habitable exoplanets.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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