In searching for the elusive Planet Nine, researchers instead turned up a different resident in our cosmic backyard.

How many Earth-like exoplanets orbit M dwarf stars (Red dwarf stars), which are smaller and cooler than our Sun? This is what ...

For the dwarf planet candidate, one trip around the sun takes over 24,000 years. Its orbit challenges a proposed path for a hypothetical Planet Nine.

Scientists may have discovered a dwarf planet far beyond Neptune — an unearthing that may disprove a longstanding theory ...

U.S. astronomers hunting for "Planet Nine" have instead stumbled on what appears to be a new dwarf planet in the solar system's outer reaches.

New Dwarf Planet Candidate Challenges What We Know About Space. Story by Ruta Kulkarni • 2h. S cientists have recently spotted a huge object far away in the cold outer reaches of our solar system.

Plus, an in-depth look at how the West Texas city of Seminole reacted when a measles outbreak tore through the region.

Less than 1% of this dwarf planet candidate's orbit is close enough to detect, which means astronomers are lucky to have caught it at all.

Scientists have discovered a new dwarf planet candidate far beyond Pluto in the solar system. Its existence could mean there's no Planet 9.

Pluto was reclassified as a dwarf planet in 2006. Our solar system may have a ninth planet after all, researchers say. The possibility that an additional planet may be hidden far into the solar ...