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

NASA administrator Jared Isaacman just urged the president to ‘make Pluto great again’—but Trump doesn’t have the power to do ...

President Donald Trump and his NASA administrator are reviving the Pluto debate again — apparently at the urging of “Star ...

February 18 marks the discovery of Pluto by astronomer Clyde W. Tombaugh. The discovery reshaped the understanding of the solar system, as Pluto was long considered the ninth planet until the ...

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

The renewed push is stirring controversy nearly two decades after the dwarf planet classification was introduced. Renewed ...

FLAGSTAFF – Clyde Tombaugh sat in the Orpheum Theater that fateful night in February 1930, waiting for clouds to pass before the 24-year-old astronomer could return to Lowell Observatory to confirm ...

On February 18, 1930, the American astronomer Clyde Tombaugh discovered Pluto! Before he discovered Pluto, another astronomer named Percival Lowell had spent over a decade trying to find it. He had ...

Flagstaff, Arizona (CNN) — For no explainable practical reason, humans are enamored with – and even empathetic toward – specific inanimate objects. Our first car. A choice coffee mug. And for a ...