The strange blend of surface chemistry on Nix and Hydra raises big question about the evolution of the Pluto system.

Regardless of whether Pluto is a planet or a dwarf planet, it remains a fascinating part of the solar system, from its huge white "heart" of frozen nitrogen to the ice-spewing 'supervolcano ...

Pluto has had a tough couple of decades. Formerly the ninth planet in our solar system, Pluto was demoted in 2006 to a “dwarf ...

A new paper discusses the possible existence of an unseen planet in the outer solar system, the so-called "Planet X" or ...

New exhibit to replace Greenbelt Planet Walk with a new trail through Julia Davis Park — but this time, with one less member ...

In astronomy, what does retrograde mean? And what connection does it have to astrology? We explain how planets move across ...

In January and February 2025, a six-planet alignment will grace the night sky, offering a celestial spectacle for skywatchers ...

which is the current classification of Pluto. The discovery of some of these dwarf planets has given us reasons to believe that something else might be lurking on the outskirts of the solar system. It ...

In the ten years preceding publication, the known solar system more than doubled in size. For the first time in almost two centuries an entirely new population of planetary objects was found. This ...

The possibility that there might be a large, unknown planet lurking in the outer Solar System far beyond Pluto has long been a staple of science fiction. But for the past decade, astronomers have been ...