Abstract

In the standard scenario for formation of planetary systems, a planetary system forms from a protoplanetary disk that consists of gas and dust. The formation scenario can be divided into three stages: (1) formation of planetesimals from dust, (2) formation of protoplanets from planetesimals, and (3) formation of planets from protoplanets. In stage (1), planetesimals form from dust through gravitational instability of a dust layer or coagulation of dust grains. Planetesimals are small building blocks of solid planets. Planetesimals grow by mutual ollisions to protoplanets or planetary embryos through runaway and oligarchic growth in stage (2). The final stage (3) depends on a type of planets. The final stage of terrestrial planet formation is giant impacts among protoplanets while sweeping residual planetesimals. In the present talk, I review the basic elementary processes of terrestrial planet formation, showing some recent simulations.