Radial migration of preplanetary material: Implications for the accretion time scale problem

Radial drift of planetesimals due to density wave interaction with the solar nebula is considered. The mechanism is most effective for large masses and provides mobility over a size range where aerodynamic drag is unimportant. The process could shorten accretion time scales to ≈O(10⁵–10⁶ years) throughout the solar system. Accumulation stalls down when growing objects are massive enough to open gaps in the gas disk. Implications of this process for current cosmogonic models are discussed.