He called this hypothetical world "Planet X." "In some ways, Pluto's more of a planet than some of the other established ...

Pluto isn't alone—it's part of the Kuiper Belt with possibly hundreds of other planet-sized objects. Because Pluto hasn't ...

Pluto was once called the ninth planet, but in 2006, scientists changed its status to a dwarf planet. A planet must clear its orbit of other objects, but Pluto shares its space with many small icy ...

Not fulfilling the second criteria, Pluto went from being the ninth planet in our solar system to one of five dwarf planets, with the IAU stating that Pluto is "an important proto-type of a new ...

The RTL-SDR dongles get most of the love from people interested in software-defined radio, but the Pluto is also a great option, too. [FromConceptToCircuit] shares code to turn one of these radios ...

Almost 10 years ago, a NASA spacecraft was able to take several photos of Pluto, known for decades as a planet before it was ...

Moons of Jupiter and Saturn are wider than Mercury, and Pluto is smaller than Earth's moon. For years, astronomers tried to define a planet by shape, orbit around a star and its influence on other ...

And if you are still a Pluto-is-a-planet holdout, like we were, [Michael]’s argument that counting all the Trans-Neptunian Objects would lead to madness is pretty convincing. It sure would make ...

This story appears in the July 2015 issue of National Geographic magazine. Small, cold, and absurdly far away, Pluto has always been selfish with its secrets. Since its discovery in 1930, the ...

Pluto, a planet that used to be one of the big nine, might have oceans under its surface. Pluto was thought to be entirely frozen over 800 million years ago but a discovery of a gaseous layer ...