How many dwarf planets are there in our solar system? The recent discovery of 2017 OF201 makes the tally anywhere between ...

Scientists have recently spotted a huge object far away in the cold outer reaches of our solar system. This 700-kilometer-wide object could be a new dwarf planet. It was discovered traveling a ...

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

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.

But Yang said more research is needed, and the discovery of the new dwarf planet candidate is not necessarily a death knell for Planet Nine.

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.

Could our solar system have 9 planets after all? Astronomers may have confirmed possible existence. Pluto was reclassified as a dwarf planet in 2006.

But Sam Deen, a 23-year-old amateur astronomer from California, has already been able to track the dwarf planet candidate through old datasets.

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 examined infrared space surveys to narrow down candidates for Planet 9. Planet 9 would be so far from the Sun that it is just not illuminated by much sunlight. The two space surveys ...

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