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The Great Pluto Debate

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The debate over Pluto’s planethood has been reinvigorated once again, thanks to a new paper co-authored by a University of Central Florida planetary scientist.

Back in 2006, the International Astronomical Union adopted new classification rules. In order for an object to be considered a planet it must be the largest gravitational force in its orbit. In Pluto’s case, its orbit is influenced by neighboring Neptune, so according to the IAU, what was once our 9th planet is no longer a planet. Instead, Pluto is classified as a dwarf planet.

Phil Metzger co-authored the paper that is re-examining the debate. He is a planetary scientist at the Florida Space Institute at UCF so he stopped by to talk about the paper and the case for classifying planets.

Brendan Byrne is Central Florida Public Media's Assistant News Director, managing the day-to-day operations of the newsroom, editing daily news stories, and managing the organization's internship program. Byrne also hosts Central Florida Public Media's weekly radio show and podcast "Are We There Yet?" which explores human space exploration, and the weekly news roundup podcast "The Wrap."