IAU Reclassifies Pluto as Dwarf Planet, Leaving 5 Official Dwarfs
Updated
Updated · Space.com · Aug 24
IAU Reclassifies Pluto as Dwarf Planet, Leaving 5 Official Dwarfs
3 articles · Updated · Space.com · Aug 24
Summary
Aug. 24, 2006 marked the IAU vote that stripped Pluto of planet status and placed it among five officially recognized dwarf planets in the solar system’s outer reaches.
The demotion hinged on a new definition requiring a planet to have cleared its orbit around the sun, a test Pluto and other distant dwarf planets do not meet.
Less than 5% of the world’s astronomers took part in the vote, according to New Horizons leader Alan Stern, who said the decision embarrassed astronomy and argued other planets also share their orbits with smaller bodies.
The ruling still shapes a live debate: keeping Pluto as a planet could force astronomers to recognize hundreds of additional planets, while public campaigns have repeatedly pushed to restore its old title.
Will the approaching 2030 centennial of Pluto's discovery trigger a scientific rebellion against the controversial rules that stripped its planetary crown?
Could Pluto's active geology and mysteriously freezing atmosphere force astronomers to finally rewrite the rules of planetary classification?
If nature ignores our labels, why are scientists still fiercely battling over Pluto's true identity twenty years after its demotion?