Pluto demoted under new definition of planet

Pluto has been considered a planet since its discovery in 1930. Under the new guidelines, it’s now considered a “dwarf planet,” leaving eight planets — Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. Pluto, which is smaller than Earth’s moon, doesn’t fit the new criteria for a planet.—Pluto demoted under new definition of planet


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