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

A team of astronomers believe they may have discovered a new dwarf planet—just like Pluto—on the edge of our solar system. The object—which orbits out beyond Neptune—has been named "2017 OF201" by the ...

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.

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 ...

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

Researchers in the US have suggested there is a 40 percent chance a ninth planet could exist in our solar system. Planet Nine ...

OF201, the object belongs to the same all-star family as Pluto: dwarf planets. Its diameter, roughly 435 miles (700 km), is ...

"We still don't know much about the solar system far away because currently ... Makemake and Eris, which all orbit beyond Neptune. The organization defines a planet and a dwarf planet differently. A ...

A team of researchers has outlined how a new "direct fusion drive" propulsion system could allow us to reach Sedna this ...