Mini-Oort clouds from giant planet scattering

Mini-Oort clouds: Compact isotropic planetesimal clouds from planet-planet scattering
http://arxiv.org/abs/1211.2809

Most likely to occur in systems with equal-mass gas giants, the scattering produces an isotropic planetesimal cloud on scales much smaller than the solar system's Oort cloud. The scattered disc in our solar system may be the remnant of a less violent scattering era:

Quote :

Finally, we note that there is an analogy between mini-Oort clouds and the Solar System’s scattered disk (Luu et al. 1997; Duncan & Levison 1997). Both contain small bodies on “fossilized” orbits and were produced during an era of planetary instability. The modest inclinations in the scattered disk show that the Solar System’s instability was far weaker than those typical of giant extrasolar planets.