  Understanding the origin and long-term evolution of the Solar System is a
fundamental goal of planetary science and astrophysics. This chapter describes
our current understanding of the key processes that shaped our planetary
system, informed by empirical data such as meteorite measurements, observations
of planet-forming disks around other stars, and exoplanets, and nourished by
theoretical modeling and laboratory experiments. The processes at play range in
size from microns to gas giants, and mostly took place within the gaseous
planet-forming disk through the growth of mountain-sized planetesimals and
Moon- to Mars-sized planetary embryos. A fundamental shift in our understanding
came when it was realized (thanks to advances in exoplanet science) that the
giant planets' orbits likely underwent large radial shifts during their early
evolution, through gas- or planetesimal-driven migration and dynamical
instability. The characteristics of the rocky planets (including Earth) were
forged during this early dynamic phase. Our Solar System is currently
middle-aged, and we can use astrophysical tools to forecast its demise in the
distant future.
