Pluto was officially reclassified as a dwarf planet in 2006 by the International Astronomical Union, which created a clear definition of what counts as a planet. To be a planet, an object must orbit the Sun, be round, and clear its orbital path of other debris. Pluto meets the first two conditions but fails the third because it shares its orbit with many objects in the Kuiper Belt. Scientists realized there were many similar icy bodies out there, so they needed a better system to classify them. Instead of calling all of them planets, they created the dwarf planet category. This change was based on scientific reasoning, not popularity or tradition. Even though many people still think of Pluto as a planet, its classification as a dwarf planet is now widely accepted in astronomy.
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