Scientists may have discovered a dwarf planet far beyond Neptune — an unearthing that may disprove a longstanding theory about the possibility of a giant ninth planet. The dwarf planet's existence ...

Though Pluto has formally been considered a dwarf planet for almost two decades, it still has many lessons left for planetary scientists — including hints about how the solar system formed.

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.

Just on the outskirts of our solar system exists the dwarf planet Quaoar, and recent observations of the planet found a dense ring around it, but scientists can't figure how – or why – it's there.

The dwarf planet also has one provisional moon, which is nicknamed MK 2. Discovery: March 31, 2005. Size: 888 miles in diameter (1/9 the size of Earth) Distance from sun: 4.3 billion miles.

A potential new dwarf planet has been discovered in the outer reaches of the solar system, and its existence poses the ...

Discovery of 2017OF201, a large trans-Neptune Object, challenges previous beliefs about the Kuiper Belt and hints at the existence of a theoretical Planet Nine.

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 ...

With this structure, the dwarf planet would get gradually muddier and less frozen at lower depths. A NASA spacecraft got a closer look at Ceres' surface between 2015 and 2018 through the ...

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 ...

On the other hand, if you’re nostalgic (and a tad antiestablishment), there are still nine now, but then, to be fair, you’d have to include the so-called dwarf planets, in which case there may ...