Topic: planetesimals

This lecture follows the growth of planets from an initial population of planetesimals. It examines collisions that build protoplanets, the accretion of smaller particles and mergers between growing bodies. Some sufficiently massive objects also capture surrounding gas, producing different classes of planets.

This lecture examines how dust in a young circumstellar disk becomes large solid bodies. Collective particle motion and its interaction with gas can concentrate material into gravitationally bound clumps. Their collapse offers a route to planetesimals, whose surviving descendants include asteroids and trans-Neptunian objects.