PULLMAN, Wash. – It’s a big week for Pluto as NASA’s New Horizons spacecraft gets a close-up look at the distant, icy world. But first, the answer to your question: Pluto is not a planet.
Scientists called it a planet when it was discovered in 1930. They needed a name for it and an 11-year-old girl living in London at the time came up with “Pluto.” Things changed in 2006.
Learn more in the complete Dr. Universe column here.
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