Dynamical evolution tracks (M_p and a) of all large planets in IGM16 simulation 1 around a solar-mass star. The different coloured solid lines represent different planets. The transparent dashed lines represent large planetesimals that merged with the planets. Sudden stepwise increases in planet masses signify these mergers. Only planets with masses >0.1 M_E are included. The cyan shaded region represents the habitable zone. The thick black ellipses in the lefthand panel highlight the first, second, and third generation of planets. IGM16 produces far more planets than OL18. Those formed as part of the third generation, after 1–2 Myr, remain in the HZ because they have insufficient time for migration.