Institute of Astronomy

Terrestrial Planet Formation and the Mixing of Planetesimal Populations

SpeakerTalk DateTalk Series
Kevin Walsh 31 July 2014Across HR 2014 Talks


Models of terrestrial planet formation in the Solar System face many more constraints than simply their masses and orbits. Rather, our knowledge of the Earth’s composition and meteorite samples on Earth provide substantial information on how the terrestrial planets were put together.  Similarly, the dynamical shape and compositional gradients of the Main Asteroid belt and other small body populations serve as strict tests for the dynamical evolution of any proposed models.
Recent models have addressed many long-standing problems of terrestrial planet formation using the dramatic migration of the giant planets early in Solar System history. These works simultaneously provide reasonable matches for constraints from both the planetary bodies and the planetesimal populations, in part due to the substantial mixing of small body populations across many AU. While such a system evolution is certainly not generic, the radial mixing of small body populations driven by the location and behavior of a system’s giant planets almost certainly is, and will strongly affect the properties of the other planets in the system.