In 2006, a vote by the International Astronomical Union determined that Pluto was no longer a planet. The decision sparked a heated public debate, and many planetary scientists disagreed with kicking Pluto out of the planet club. Twenty years later, Pluto is back in the news: NASA administrator Jared Isaacman said he wants to make Pluto great again by declaring it… a planet again. And he’s urging President Trump to do so by executive order. Why does this Plutonian debate keep rearing its head? And does the president have the power to do that? To answer those questions and more, Host Ira Flatow talks with planetary scientists and Pluto champions Amanda Bosh and Alan Stern. Guests: Dr. Amanda Bosh is the executive director of the Lowell Observatory in Arizona, where Pluto was first discovered. Dr. Alan Stern is the vice president at the Southwest Research Institute and principal investigator of the New Horizons mission to Pluto. Transcripts for each episode are available within 1-3 days at sciencefriday.com. Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

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“What did the council decide on item 42?” — answered with the speaker and the moment.