One-hour lecture , followed by the seminar.
Abstract
The new versions of the Nice model are based on the observation that the orbits of the giant planets should be in mutual resonance at the moment of gas dissipation, after the migration phase induced by gas-planet interactions within the protoplanetary disk. Unlike the first version of the model, the initial conditions of the planets are not arbitrary. In the current version of the Nice model, Jupiter and Saturn are initially in a 3:2 resonance (their orbital period ratio is equal to 1.5), while Uranus and Neptune can be in different resonances (2:1, 3:2, 4:3, etc.). The existence of a fifth planet with a mass comparable to Neptune's is also sometimes postulated. The rupture of this resonant chain, caused by interactions with planetesimals, triggers the phase of dynamical instability of the planets. Current planet orbits can be reproduced in a significant fraction of simulations.