Is Pluto still a planet?

No.Pluto was reclassified as a dwarf planet in 2006 by the International Astronomical Union. It orbits in a region beyond Neptune where other objects can cross its orbital path, so it doesn't meet the full definition of a planet.

What's actually true

Pluto has been a dwarf planet since 2006. In 2006 the International Astronomical Union, the body that names things in space, set out what counts as a planet and reclassified Pluto as a dwarf planet. One reason: Pluto shares its zone of space, beyond Neptune, with many other icy objects that can cross its path. Pluto didn't shrink or change. Astronomers found more worlds like it, and the definition caught up.

Takeaway: Officially, Pluto has been a dwarf planet since 2006. It didn't change; our definition of 'planet' did.

Why people believe it

For generations Pluto was taught as the ninth planet, and many of us learned a mnemonic that ends with it. The 2006 decision felt like a demotion, and people still argue about it, so 'Pluto is a planet' never fully went away. The change came after astronomers found other icy worlds of a similar size in the same distant region.

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