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Why is Ceres classified as a dwarf planet?

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Illustration showing a massive asteroid above a city map with a dinosaur silhouette for scale, highlighting the asteroid's size compared to major urban areas. — Asteroid This rock would take out more than just a *T. rex*.

Ceres is classified as a dwarf planet because it meets specific criteria established by the International Astronomical Union (IAU) in August 2006.12

To be categorized as a dwarf planet, a celestial body must satisfy the following conditions:
* It orbits the Sun.2
* It is not a natural satellite (moon).2
* It possesses sufficient mass for its own gravity to have pulled it into a substantially rounded shape.2
* It has not cleared its orbital neighborhood of other debris, meaning it is not massive enough to have gravitationally dominated its surroundings to sweep up smaller nearby bodies.2

While Ceres remains the largest asteroid in the main asteroid belt, its size and shape—a flattened sphere—led the IAU to include it in this new category alongside objects like Pluto and Eris. Unlike other dwarf planets, which are often classified as plutoids due to their location beyond Neptune, Ceres is unique because it resides within the asteroid belt.12