The process of demoting Pluto began in 2005 when a dwarf planet named Eris was discovered in a region outside of Neptune’s orbit in the same belt as Pluto. Because this dwarf planet, Eris, was actually larger than Pluto, it created complications with classification. This was when the International Astronomical Union (IAU) decided officially that Pluto needed to be downgraded from a full sized planet, which took place on August 24, 2006 in Prague, Czech Republic.
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