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Which requirements must an object meet to be classified as a planet by the International Astronomical Union?

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Illustration showing the eight planets of the solar system in order from the Sun-Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune-depicted to scale by size, with labeled diameters in miles and kilometers. The Sun is partially visible on the left for comparison. — Solar system The planets (in comparative size) in order of distance from the Sun.

To be classified as a planet within our solar system by the International Astronomical Union (IAU), a celestial body must satisfy three specific criteria established in 2006:123

Orbit the Sun: The object must be in orbit around the Sun.13
Hydrostatic Equilibrium: The object must have sufficient mass for its own gravity to overcome rigid body forces, assuming a nearly round (spherical) shape.123
Clear the Neighborhood: The object must have cleared the neighborhood around its orbit, meaning its gravitational dominance has removed other rocky and icy debris from its orbital vicinity.23

If an object meets the first two criteria but fails to clear its neighborhood, it is classified as a dwarf planet, provided it is not a moon of another body. Pluto was reclassified as a dwarf planet because it orbits within the Kuiper belt and has not cleared its orbital path.32