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Was Pluto’s 2006 demotion a mistake?

scienceAug 31, 202639110

Twenty years after the International Astronomical Union voted in August 2006 to reclassify Pluto from a major planet to a dwarf planet, a vocal movement is campaigning to restore Pluto’s planetary status. Critics led by scientists such as Philip Metzger say the IAU’s three-part definition of a planet makes the category scientifically useless, with Metzger saying “you can’t use it at all.” Supporters including Laurel Kornfeld and historian Kevin Schindler frame Pluto’s demotion as wrong and emotionally resonant, and the campaign has been strongest in the United States. The 2006 vote was prompted by the discovery of Eris in the Kuiper Belt, a body similar in size to Pluto, and by the subsequent identification of other distant objects such as Haumea, Makemake and Sedna. The IAU definition requires orbiting the Sun, being round from self-gravity, and having cleared the neighbourhood, and it is that last criterion that excludes Pluto because the Kuiper Belt contains many similar objects. Restoring Pluto as a planet would force astronomers to decide whether to add hundreds of Kuiper Belt bodies to the planet roster, with implications for classification and school teaching. The debate has occasionally attracted political attention, including an April comment from NASA administrator Jared Isaacman saying he supports rethinking Pluto’s status.

Revan
@revan.eurosky.social

Two things can both be true: The reasons Pluto was demoted from planet were extremely petty The people fighting to reverse it are embracing toxic nostalgia and LOOK WHAT THEY TOOK FROM YOU

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