Kuiper belt objects which, like Pluto, have semi-major axes of AU and are is a 3:2 orbital resonance with Neptune. Some are also in Neptune-crossing orbits, like Pluto. Of the 32 observed Kuiper belt objects (plus Pluto itself), Jewitt and Luu have identified 13 plutinos. A complete list is maintained by Jewitt. Jewitt and Luu estimate that there are a total of plutinos in all.

Kuiper Belt