Dynamical origin of the solar system

A quantitative model of the primordial solar nebula is outlined using which the distribution of temperature, density, pressure, thickness, and mass transfer rate of the nebula can be determined at any given epoch. Observational data, such as the spatial and mass distribution of the planets, as well as meteorite data, are utilized to provide constraints on the model. The most favorable scenario is one in which the protogiant planets formed through several stages of coagulation, accumulation, and accretion. The final epoch, when the protoplanets acquired most of their mass, must have lasted less than about a million years. During this epoch, the solar nebula was considerably less massive than the present sun