In collaboration with Vacheslav Emel'yanenko (South Ural University, Russia), David Asher and Mark Bailey have continued their research on bodies in the outer part of the solar system, beyond the orbit of Neptune. Previously they had identified a new class of orbit in that region, stable over the lifetime of the solar system. Now they are investigating more unstable orbits, in particular the question of where bodies on such orbits can dynamically evolve to. There are dynamical routes through the Centaur region occupied by the outer planets, to the family of Jupiter comets often observed from Earth. Objects of high orbital eccentricity in trans-Neptunian space are found to be a significant source of Jupiter family comets. It is also concluded that the primordial number of such trans-Neptunian objects was substantially larger than at present.