标题： 木卫一的部分微分作为可能的尘埃凝聚的证据 显示英文标题

标题： Partial Differentiation of Callisto as Possible Evidence for Pebble Accretion

摘要： “星子或尘埃”是行星形成理论中最重要的基本未解问题之一。 同样，“卫星星子或尘埃”在伽利略卫星的形成方面仍未解决。 我关注的是卡利斯托的一个独特特征——根据重力场测量，其内部估计仅部分分化。 我强有力地证明，这种状态无法通过卫星星子吸积实现，这不可避免地导致显著的分化，但可以通过尘埃吸积维持。 尘埃可以在卫星表面释放其撞击能量，从而实现有效的辐射冷却，且它们的撞击速度可通过围绕行星的气体盘的空气动力学阻力降低。 如果未来的任务，如木星冰 moons 探测器（JUICE）确认卡利斯托确实仅部分分化，这可能为尘埃吸积机制提供首个观测证据——不仅在卫星形成的背景下，而且在更广泛的行星形成框架中。 显示英文摘要

摘要： "Planetesimal or pebble" is one of the most fundamental open questions in planet formation theory. Similarly, "satellitesimal or pebble" remains unsettled regarding the formation of the Galilean satellites. I focus on a unique characteristic of Callisto--its interior is estimated to be only partially differentiated based on gravitational field measurements. I robustly demonstrate that such a state is not achievable through satellitesimal accretion, which inevitably leads to significant differentiation, but can be maintained with pebble accretion. Pebbles can release their impact energy at the surface of the satellite, allowing efficient radiative cooling, and their impact velocities can be reduced by aerodynamic drag from the circumplanetary gas disk. If future missions such as JUpiter ICy moons Explorer (JUICE) confirm that Callisto is indeed only partially differentiated, it could provide the first observed evidence for the pebble accretion mechanism--not only in the context of satellite formation, but also in the broader framework of planet formation.