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The International Astronomical Union, a group of 9,000 astronomers from around the world, decided on the three conditions necessary for a body to be called a planet. First, it must orbit around the sun. A planet must also be big enough for its own gravity to maintain a round shape. Finally, to be classified as a planet, it must not cross into the orbit of any of its neighbors. Even without Pluto, scientists surely will continue to study the planets.
What is concept/definition?