Tidal disruption of satellites and formation of narrow rings Disruption of satellites
Tidal disruption of satellites and formation of narrow rings Disruption of satellites
复制标题
卫星的潮汐破坏和狭窄环的形成 卫星的破坏
DOI：
10.1111/j.1365-2966.2012.21328.x
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发表时间：
2012
影响因子：
4.8
通讯作者：
Leinhardt Z
中科院分区：
文献类型：
--
作者：
Leinhardt Z
在本文中，我们研究了狭窄的行星环的形成，如天王星和土星周围发现通过潮汐破坏的弱，引力约束的卫星，迁移在其罗氏极限。usingN体模拟，我们研究的行为放置在圆形轨道上的碎石堆在不同的距离从中央行星。我们认为，均质卫星和分化机构包含一个更密集的核心。我们表明，罗氏极限的碎石堆是更接近地球比一个流体的平均密度相同。一个分异天体的洛希极限也比一个平均密度相同的同质卫星更接近行星。在洛希极限内，同质卫星完全分裂，形成一个狭窄的环。破裂的初始阶段类似于粘性流体椭球的演化，可以半解析地计算。另一方面，当一个分化的卫星只是在洛希极限内，只有地幔被破坏。这个过程类似于交互作用双星中的洛希瓣溢出，并在残留卫星的两侧产生两个狭窄的环。我们认为，天王星环，可能是他们的牧羊人卫星，可能已经形成了通过潮汐破坏的一些原月亮内形成的天王星的共转半径和迁移缓慢向内作为潮汐相互作用的结果与行星。
In this paper, we investigate the formation of narrow planetary rings such as those found around Uranus and Saturn through the tidal disruption of a weak, gravitationally bound satellite that migrates within its Roche limit. UsingN-body simulations, we study the behaviour of rubble piles placed on circular orbits at different distances from a central planet. We consider both homogeneous satellites and differentiated bodies containing a denser core. We show that the Roche limit for a rubble pile is closer to the planet than for a fluid body of the same mean density. The Roche limit for a differentiated body is also closer to the planet than for a homogeneous satellite of the same mean density. Within its Roche limit, a homogeneous satellite totally disrupts and forms a narrow ring. The initial stages of the disruption are similar to the evolution of a viscous fluid ellipsoid, which can be computed semi-analytically. On the other hand, when a differentiated satellite is just within the Roche limit only the mantle is disrupted. This process is similar to Roche lobe overflow in interacting binary stars and produces two narrow rings on either side of a remnant satellite. We argue that the Uranian rings, and possibly their shepherd satellites, could have been formed through the tidal disruption of a number of protomoons that were formed inside the corotation radius of Uranus and migrated slowly inwards as a result of tidal interaction with the planet.