Astronomers find evidence of a possible ninth planet beyond Neptune, reigniting the debate about the formation of the Solar ...

With Pluto's "demotion" to dwarf planet status, it’s understandable that the IAU faced criticism from the public for ...

Pluto may have lost its status as a full-fledged planet in 2006, but that doesn't mean it's a joke of a world this April Fools' Day and the folks behind Pluto TV want to make that clear.

Pluto Fire initially started 2:20 p.m. May 24 in Siskiyou County. Since its discovery 41 hours ago, it has burned 12 acres.

It’s been 18 years since Pluto’s celestial status was called into question—yet the matter seems far from settled. We asked experts from both sides to make their case. This 2015 NASA image of ...

Pluto, humanity's favorite dwarf planet, is getting some high-profile allies. "Star Trek" actor William Shatner wants to use ...

Pluto Fire initially started 2:20 p.m. May 24 in Siskiyou County. Since its discovery 29 hours ago, it has burned 12 acres.

(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?

As Pluto passed in front of those far-away stars, their light shining through its atmosphere offered clues as to its status. Using this data, scientists were able to track a dramatic increase in ...

Despite the change, Pluto remains a beloved celestial body, and some astronomers still debate whether it should regain its planetary status. Yes. Clyde Tombaugh discovered Pluto on Feb. 18 ...

In 2006, the International Astronomical Union stopped classifying Pluto as our solar system’s ninth planet and demoted its ...

This sparked debate about Pluto's status in the planetary canon, which came to a head at a 2006 meeting in Prague. That year, the IAU tasked a small committee with creating a working definition of ...