Formal minor-planet designations are number-name combinations overseen by the Minor Planet Center, a branch of the IAU. They are used for dwarf planets and small Solar System bodies such as asteroids, but not comets. They are assigned to a body once its orbit is secured, and are unrelated to provisional designations, which are automatically assigned when an object is discovered.

Pluto (minor-planet designation: 134340 Pluto) is a dwarf planet in the Kuiper belt, a ring of bodies beyond the orbit of Neptune.

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