KUIPER BELT OBJECT
A Kuiper belt object is a small body or remnant from the formation of a star system, located in a vast belt in the far reaches of the system. Unlike an asteroid, which is typically made of mineral and rock, a Kuiper belt object is composed primarily of frozen volatiles such as methane, ammonia, and water. These bodies are typically small, measuring no more than 100 kilometers in diameter.
CLASS C: CUBEWANO
A cubewano is a common Kuiper belt object with a relatively circular orbit that is not influenced by nearby planets, and a low-inclanation--meaning that it orbits on the same general plane as the rest of the planets in the star system..
CLASS D: DETACHED
Also known as a Sednoid, a detached Kuiper belt object is sufficiently distant from the gravitational influences of nearby planets, and therefore assumes an eccentric orbit that makes it appear detached from the rest of the solar system.
CLASS P: PLUTINO
Plutinos are a dynamic group of Kuiper belt objects that form the innermost part of the belt. They reside close enough to a major planet to have orbital resonance with the larger body; for example, in the Solar System, most Plutinos orbit the sun twice for every three orbits of the planet Neptune.
CLASS T: TWOTINO
The outermost reaches of a Kuiper belt contain the lowly twotinos. They tend to have orbits with moderate eccentricity and inclination. Though it is a common misconception, they have nothing to do with pizza rolls.