On August 24, 2006, the International Astronomical Union voted to redefine the term “planet,” which led to Pluto’s reclassification as a dwarf planet. The decision followed discoveries of other small bodies in the outer solar system similar in size to Pluto. While the meeting took place in Prague, the change sparked especially strong reactions in the United States, where Pluto’s 1930 discovery had been celebrated. American educators and students debated how to adjust textbooks and lessons. The reclassification prompted public discussion about how scientific definitions evolve. NASA missions like New Horizons later renewed interest in Pluto’s complex geology and atmosphere.
