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

After passing Pluto, the craft will continue into the farthest reaches of the solar system. Scientists suspect there may be yet more moons around Pluto, some perhaps sharing or swapping orbits and ...

The trans-Neptunian object Altjira, 44 times farther from the Sun than Earth is, could be the second known trinary, ...

FLAGSTAFF, Az. – Whether Pluto is officially a planet is the least interesting thing about the runt of the solar system, astronomers will tell you 95 years after the discovery of the fascinating ...

A powerful new observatory is the best hope yet for finding the elusive Planet 9, a large planet that some scientists say is ...

than any of the planets in the outer solar system. Nevertheless, because it orbited the Sun like a planet, it was classified as a planet and named Pluto, after the god of outer darkness in Roman ...

Pluto isn’t the only dwarf planet in our solar system's outer reaches. Now is an ideal time to look for the egg-shaped Haumea, says Abigail Beall ...

The relative quantities of volatile gases like methane and ethane can reveal key details about distant Kuiper Belt objects.

Flyby New Horizons Pluto Solar System Spacecraft Get the best tech, science, and culture news in your inbox daily. News from the future, delivered to your present. Please select your desired ...

This image of Pluto, one of 77 composite photographs that appeared in Otherworlds: Visions of our Solar System, shows the dwarf planet lit from behind by the Sun, surrounded by a tenuous, hazy blue ...