论文标题
鹅卵石木彗星的热惯性67p/churyumov-gerasimenko
Thermal inertias of pebble-pile comet 67P/Churyumov-Gerasimenko
论文作者
论文摘要
罗塞塔（Rosetta）的67p/churyumov-gerasimenko彗星任务提供了新数据，以更好地了解彗星的制造。彗星表面材料的弱拉伸强度表明，彗星是通过在气态太阳星云中所谓的``鹅卵石''的绑定的小灰尘聚集体的重力崩溃而形成的分层灰尘骨料。由于卵石是彗星的组成部分，它们是太阳星云中行星的幸存者，因此使用热观测和数值计算的组合估算了卵石的大小，对于理解外太阳系中的行星形成至关重要。在这项研究中，我们计算了鹅卵石分层骨料的热惯性和热皮肤深度，用于温度的昼夜和轨道变化。我们发现，彗星67p/churyumov-gerasimenko的热惯性与CM-至DM大小的卵石的层次骨料一致。我们的发现表明，冰冷的行星可能是通过太阳星云中的CM-至DM大小的卵石形成的。
The Rosetta mission to comet 67P/Churyumov-Gerasimenko has provided new data to better understand what comets are made of. The weak tensile strength of the cometary surface materials suggests that the comet is a hierarchical dust aggregate formed through gravitational collapse of a bound clump of small dust aggregates so-called ``pebbles'' in the gaseous solar nebula. Since pebbles are the building blocks of comets, which are the survivors of planetesimals in the solar nebula, estimating the size of pebbles using a combination of thermal observations and numerical calculations is of great importance to understand the planet formation in the outer solar system. In this study, we calculated the thermal inertias and thermal skin depths of the hierarchical aggregates of pebbles, for both diurnal and orbital variations of the temperature. We found that the thermal inertias of the comet 67P/Churyumov-Gerasimenko are consistent with the hierarchical aggregate of cm- to dm-sized pebbles. Our findings indicate that the icy planetesimals may have formed via accretion of cm- to dm-sized pebbles in the solar nebula.
