The debate over Pluto’s planetary status has been ongoing since its reclassification as a “dwarf planet” in 2006 by the International Astronomical Union (IAU). Recent discussions and new scientific ...

Pluto was downgraded from a planet to a dwarf planet in 2006 by the International Astronomical Union. NASA Administrator Jared Isaacman has stated his support for President Trump to take action to ...

Editor’s note: A version of this story originally appeared in Astronomy’s 2007 special issue 50 Greatest Mysteries of the Universe. For a more recent discussion of Pluto’s planethood, see “An ...

This voice experience is generated by AI. Learn more. This voice experience is generated by AI. Learn more. NASA Administrator Jared Isaacman testifies during a House budget hearing at the Rayburn ...

Pluto was downgraded from a planet to a dwarf planet in 2006 by the International Astronomical Union. The main reason for Pluto's demotion is that it's not able to "clear its orbit of debris." Other ...

(Correction: An earlier version of this story misstated how far Pluto is from the sun. The correct number is 3.7 billion miles.) What was discovered in Flagstaff, Arizona, and killed off in Prague? If ...

Pluto was discovered at Lowell Observatory in Flagstaff, Arizona in 1930 and was considered our ninth planet until 2006. The International Astronomical Union reclassified Pluto as a dwarf planet ...