後期重轟炸期
The timing of the instability in the Nice model was initially proposed to have coincided with the Late Heavy Bombardment, a spike in the impact rate thought to have occurred several hundred million years after the formation of the Solar System. However, recently a number of issues have been raised regarding the timing of the Nice model instability, whether it was the cause of the Late Heavy Bombardment, and if an alternative would better explain the associated craters and impact basins. Most of the effects of the Nice model instability on the orbits of the giant planets and those of the various small body populations that originated in the outer planetesimal disk are independent of its timing, however.