Evolution of the outer solar system from the formation of Uranus and Neptune

Abstract

The formation of Uranus and Neptune is one of the great challenges of the planetary formation models. Most models assume that supermassive planetary embryos exist beyond Saturn's orbit, and by colliding with each other and/or accreting particles with sizes of cm and mm (known as pebbles) give rise to the Uranus and Neptune cores shortly before the solar nebula dissipation. The models fail to obtain all the characteristics of the ice giants planets, such as: mass ratio, obliquity, rotation and internal properties. In this project, we will use N-body simulations to study the initial stages of formation of planetary embryos through dust coagulation, planetesimal accretion and pebble accretion. Then, starting from the formed embryos we will simulate the final phase of the ice giants planets formation seeking to reproduce the characteristics cited above. Models of solar system dynamical evolution suggest that the giant planets had more compact orbits in the past, forming a resonant configuration. In addition, as a remnant of planetary formation in the solar system, a disk of planetesimals extended beyond Neptune's orbit. A dynamical instability between the giant planets and the planetesimal disk sculpted the orbits of the current external solar system. However, the solar system evolution theories still contain many open questions such as the time of instability or how many giant planets were formed. In conjunction with the formation of the ice giants planets, we intend to simulate the planetesimal disc formation. Finally, we will simulate the evolution of the formed systems after the gas dissipation, analyzing the period of instability and the configuration of the systems that reproduce the outer solar system. (AU)