NASA’s New Horizons mission has answered one of the most basic questions about Pluto — its size. Mission scientists have found Pluto to be 1,473 miles (2,370 kilometers) in diameter, somewhat larger ...

Mission scientists have found Pluto to be 1,473 miles (2,370 kilometers) in diameter, somewhat larger than many prior estimates. Images acquired with the Long Range Reconnaissance Imager (LORRI) were ...

In a universe full of planets, 2007 OR10 is something special. It’s big, just slightly smaller than the size of Pluto. And it’s close, within our very own solar system. So how did it still manage to ...

At a press conference, New Horizons' top dog Alan Stern just announced that his team has calculated Pluto's most accurate diameter yet: about 1,473 miles from one end to the other, give or take 12 ...

LAUREL, Md. — With less than 24 hours to go before NASA's New Horizons probe makes its close flyby of Pluto, scientists are already learning more about the dwarf planet than ever before, including the ...

Pluto has long been one of the most debated celestial bodies in our solar system. Once classified as the ninth planet, it was redefined in 2006 as a dwarf planet, a decision that still sparks ...

In 2006, several months after New Horizons launched into space, Pluto stopped being a planet. That was according to the world's top astronomers, who said the celestial body failed to meet one of the ...