Astronomers using the Hubble Space Telescope have discovered a fourth moon orbiting Pluto. Pluto - for the record - is still classified as a dwarf planet. Astronomer Larry Wasserman of Lowell ...

Planetary scientist Adeene Denton runs computer simulations to investigate Pluto, the moons of Saturn and other icy bodies in the solar system.

Pluto may have been demoted to non-planet status, but it still commands a court of five moons, as is fitting for the king of darkness; after all, Pluto is the Roman equivalent of the Greek God Hades.

Some 4.5 billion years ago, the dwarf planet Pluto was suddenly joined by a companion. For a brief period – perhaps only hours – they danced as if arm in arm before gently separating, a grand do-si-do ...

Is a sun a star or a planet? While science now agrees the sun is a star, new telescopes may soon challenge how we define ...

Pluto is no longer classified as a planet, it’s a dwarf planet, however, it still has five moons. Now astronomers say they have detected CO2 and other compounds on one of its moons for the first time ...

Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. For decades ...

Back in the 1980’s, a now-defunct magazine called Science Digest held a contest to name Planet X — the still-undiscovered world that astronomers believed might lie out beyond Pluto. One of the best ...

Scientists have detected methane gas glowing faintly above Makemake, an icy dwarf planet smaller and farther than Pluto in space. Until now, Pluto was the only object that far out in the solar system ...