Is there a massive undiscovered planet on the outer reaches of the solar system? The idea has been around since before the ...

Astronomers have long speculated about the existence of a mysterious planet lurking far beyond Neptune, a world several times ...

For reference, Pluto’s average distance from the Sun is about 40 AU, so 2023 KQ14 is quite distant. At 23.4 billion miles (37 ...

The discovery was made by astronomers using the Subaru Telescope, which is situated atop a dormant volcano in Hawaii.

A newly discovered dwarf planet called 'Ammonite' (2023 KQ14) has been spotted in the outer solar system, and it could be ...

Because Pluto is so dim, you need a telescope to see it. “A backyard telescope could do it under the right conditions,” says ...

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.

Over the past decade, researchers have been puzzling through Pluto’s mysteries. Meanwhile, the New Horizons probe heads for interstellar space.

But why isn't Pluto considered a planet anymore? It starts with the definition of a planet — or lack thereof. Before 2006, there weren't strict criteria for a planet.

Rep. Justin Wilmeth is advocating for the Pluto to become Arizona's state planet. The bill is now in Gov. Katie Hobbs' hands. Here's what to know.