NASA's New Horizons mission has answered one of the most basic questions about Pluto—how big is it? Mission scientists have found Pluto to be 1,473 miles in diameter, somewhat larger than many prior ...

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 ...

A new simulation of Pluto's upper atmosphere shows that it extends so far from the planet that stray molecules may be deposited on its largest moon, Charon. The new model predicts that Pluto's ...

Pluto's largest moon, Charon, likely formed through a capture event in the early, crowded Kuiper Belt. Three-body encounters ...

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 ...

Journey beyond Neptune to uncover the frozen, mysterious worlds that challenge everything we thought we knew about the solar ...

Pluto has just been found to be ever so slightly bigger than we thought, having a diameter of 2,370km. The measurement was made by the New Horizons probe which is just about to flyby the dwarf world.