Debate has raged for two decades over whether Pluto should be considered a planet. Some want President Trump to take action via executive order.

Discovered in 1930 at the Lowell Observatory, Pluto was demoted as a planet in 2006. Some want President Trump to take action via executive order.

A new formation theory for Pluto's moon Charon could explain why Pluto is geologically active. Illustration incorporates NASA New Horizons terrain imagery. Pluto — demoted to dwarf planets status in ...

Hundreds of people who love the little planet that was dissed, gather every year in the Arizona town where Pluto was ...

It’s been 18 years since Pluto’s celestial status was called into question—yet the matter seems far from settled. We asked experts from both sides to make their case. This 2015 NASA image of Pluto ...