Constraining planetesimal-formation models by comet observations

两个主要的微行星形成的场景-重力湍流的卵石云崩溃和碰撞质量吸积-应根据预测的物理性质产生的微行星的特点。我们将确定和量化尽可能多的星子属性，并研究是否以及在何种程度上演化过程可能已经改变了这些属性之间的星子形成和今天在这些地区的原行星盘和柯伊伯带的短周期彗星起源。与此同时，我们将从彗星的观测和任务中确定可用的观测量和工具，以确定彗星核的等效物理特性。最后，我们将讨论是否以及在何种条件下，一个明确的决定的形成方案的星子是在所有可行的彗星和彗星核的当前和预期的未来观测。拟议的项目包括与国际上著名的星子形成和演变方面的同事以及彗星观测和建模方面的专家进行的许多合作。除此之外，还计划举办一次关于星子形成的国际讲习班，作为该项目的一部分。

The two main planetesimal-formation scenarios – the gravoturbulent collapse of a pebble cloud and the collisional mass accretion – shall be characterized with respect to the predicted physical properties of the resulting planetesimals. We will determine and quantify as many as possible planetesimal properties and study whether and to which extent evolutionary processes might have altered these properties between planetesimal formation and today in those regions of the protoplanetary disk and the Kuiper Belt from which short-period comets originate. In parallel, we will identify useable observables and tools from observations of and missions to comets to determine the equivalent physical properties of cometary nuclei. Finally, we will discuss whether and under which conditions an unambiguous determination of the formation scenario of planetesimals is at all feasible with current and anticipated future observations of comets and cometary nuclei. The proposed project encompasses numerous collaborations with renowned international colleagues on planetesimal formation and evolutions as well as with experts on comet observations and modelling. On top of that, an international workshop on planetesimal formation is planned that will be organized as part of this project.