Growth and interaction of planets

Abstract

We discuss theories of origin and evolution of the newly discovered extrasolar planetary systems. As these systems failed to fulfill prior expectations concerning their orbital structure, we are challenged to extend and/or revise many preexisting theories. Important extensions include migration of bodies in disks and planetary eccentricity pumping by planet-planet interaction and primordial disk-planet interaction. Progress in observational techniques will allow us to find which of these two types of interaction is responsible for the observed variety of orbits and masses of planets. New insights into the formation of giant planets in our system can be obtained by asking why Jupiter and Saturn are not larger, closer to the sun and/or do not follow noticeably elliptic orbits.