The first step in planet formation is to build planetesimals from dust particles in protoplanetary disks. The origin and demographics of planetesimals are crucial to understanding the Solar System, exoplanetary systems, and circumstellar disks. In this talk, I will present our latest works on planetesimal formation via the streaming instability, a mechanism to aerodynamically concentrate dust particles and produce planetesimals. I will also discuss the implications and connections between our high-resolution simulation results and recent disk observations, as well as Solar System explorations.
