In astronomy, a plutino is a Pluto-like object, insofar as it has the same relative orbit as Pluto. These orbits are stabilized by an orbital resonance with Neptune, similar to Pluto's 3:2 orbital resonance. This means that plutinos complete 2 orbits around the sun in the time it takes Neptune to complete 3 orbits. Plutinos form the inner part of the Kuiper belt. About 1/4 of known Kuiper Belt objects are Plutinos.

Some known plutinos:

• Charon, the moon of Pluto
• 28978 Ixion
• 90482 Orcus

Since Pluto fits the 3:2 orbital resonance, it is sometimes convenient to include Pluto itself when referring to that orbital category of objects as plutinos. However, others argue that because "plutino" means "little Pluto", Pluto itself can't be a "little Pluto".

External link

• David Jewitt (Univ. of Hawaii) on Plutinos