17 mars 2017
The first gravitationally bound bodies to form in protoplanetary disks, the 1-100 km sized planetesimals, are a key intermediate step in planet formation. After decades of uncertainty, at least one viable path to planetesimal fomation – based on radial drift of small solid particles, the streaming instability, and gravitational collapse – has now been securely established. I will discuss numerical simulations of planetesimal formation, and their (speculative) implications for planetary system architecture. I will argue that the somewhat restrictive conditions for planetesimal formation constitute a key bottleneck in the planet formation process, that can link variable disk properties to the architecture of resulting planetary systems.