Interaction of Unstable System with a Trans-Saturnian Disk (Thommes et al 1999; 2001) Cores (Uranus and Neptune) scattered outward and orbits circularized due to interactions with disk.
Jupiter, Saturn, Uranus and Neptune at roughly their current locations.
Could explain why D/H of Uranus and Neptune is different from comets.
May explain the a-e distribution of the main KB.
Objects rain down on Earth and Moon Late Heavy Bombardment .