24 January 2008

Speaker: Alessandro Morbidelli (Observatory of Nice, France)

Title: Crucial Dynamical Phases in Solar System Formation

Abstract:

The formation and evolution of the giant planets of our Solar System presents several problems: the cores of the planets should have been driven into the Sun by Type I migration, faster than they could accrete their massive gaseous atmosphere; once formed, Jupiter and Saturn should have suffered Type-II migration towards the Sun, becoming hot or warm giants, like most of the extra-solar planets known so far; the planets most likely underwent a late reorganization of their orbital architecture, as indicated by the Late Heavy Bombardment (LHB) of the Moon, which suggests that a massive reservoir of small bodies suddenly became unstable.

Without pretension of providing any definitive answer, I will present a scenario of the formation and evolution of the giant planets that addresses these problems. More specifically I will present simulations of the dynamics of planetary cores in the vicinity of a `planet trap', which can exist at the transition between the active and the dead zones of the disk. I will illustrate how the dynamics of the fully formed planets in the gas disk leads to one of 6 possible mutual configurations, that are stable and avoid significant migration towards the Sun. Finally I will describe our model for the origin of the LHB and how it connects with some of these mutual stable configurations.

Video of the Presentation (Talks can be viewed with RealPlayer. Free download is available from www.real.com )