The Changing Perception of the Solar System

Abstract: The solar system has changed dramatically since its birth, and so did our understanding of it. A considerable research effort has been invested in the past decade in an attempt to reconstruct the solar system history, including the earliest stages some 4.5 billion years ago. The results indicate how several processes, such as planetary migration and dynamical instabilities, acted to relax the orbital spacing of the outer planets, and provided the needed perturbation to explain the present planetary orbits that are not precisely circular and coplanar. Here we highlight this work and illustrate the key results in a computer simulation that unifies several recently developed theories. The emerging view represents another step away from the initial perception of the solar system as part of unchanging heavens.