Abstract The dynamically founded model of the origin of planets is based on two main concepts: (1) the common formation of the Sun and planets from the same gas-dust cloud; and (2) the accumulation of planets from solid bodies and particles. In the solar nebula of a moderate mass there were no conditions for the formation of large gaseous protoplanets. At the end of collapse and the decay of turbulence, the dust component of the protoplanetary disc precipitated towards its central plane forming a dust layer which disintegrated into numerous condensation centres. After a short collisional evolution they transformed into solid bodies of different sizes. Larger bodies contained a major part of the total mass of solid material, and their gravitational perturbations increased the velocities of the bodies. The largest bodies grew faster than the others and became embryo-planets that swept out all solid material. The accumulation of terrestrial planets was grossly homogeneous and lasted 100 Ma. The surfaces of growing planets were subject to an intensive impact transformation and heating. While in the central region of the Earth the temperature was several times less than the melting temperature, the upper mantle was heated by impacts of the largest bodies (of asteroidal size) until the beginning of the melting of rocks. At the end of the accumulation the mean surface temperature was about 300 K. Mega-impacts created large-scale inhomogeneities in the upper mantle with pools of melted material where differentiation began. Within the first 1 Ga a core, a hydrosphere and an atmosphere comparable in mass with the present ones had formed providing conditions for the origin of prebiological compounds.