A new tiny ice world has been discovered beyond Pluto surrounded by a thin atmosphere, scientists revealed.

Two decades ago, the International Astronomical Union—which defines and names celestial bodies—redefined the criteria for ...

Pluto was believed to be the only body beyond Neptune with an atmosphere. Now, a new discovery in our solar system is ...

A gradual dimming and brightening when a star passed behind it suggested the mini-Pluto was wrapped in a thin layer of air.

The problem with Pluto isn’t its planetary or nonplanetary status—it’s our insistence on declaring the world must be one or the other ...

Pluto was downgraded from a planet to a dwarf planet in 2006 by the International Astronomical Union. The main reason for Pluto's demotion is that it's not able to "clear its orbit of debris." Other ...

A rare observation opportunity revealed the presence of a thin atmosphere around a small object beyond Pluto.

Scientists have recently unveiled a remarkable discovery in the outer reaches of our solar system: a space fossil located 4 billion miles past Pluto, covered in unidentified organic molecules. This ...

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 ...