A possible new dwarf planet has been discovered at the edge of our solar system, so far-flung that it takes around 25,000 ...

The object’s aphelion—the farthest point on the orbit from the sun—is more than 1,600 times that of Earth’s orbit,” Institute ...

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.

The small world was found during a search for the hypothetical Planet Nine, and astronomers say the next time it will reach ...

For the unversed, "Planet Nine" is a hypothetical planet which is reportedly larger than Earth that is thought to orbit ...

The International Astronomical Union’s Minor Planet Center, which catalogs new moons and other small bodies in the solar ...

There’s a new object in the distant reaches of our solar system, and it might just offer clues to a long-standing cosmic ...

It's an evocative idea that has long bedeviled scientists: a huge and mysterious planet is lurking in the darkness at the ...

Researchers discovered a new trans-Neptunian object, 2017 OF201, potentially a dwarf planet, in the outer solar system.

The newly discovered object, named 2017 OF201, has a 25,000-year orbit and is believed to be a large contender for dwarf ...

As it orbits the sun once every 25,000 years, the celestial body 2017 OF201 travels beyond the Kuiper Belt into a region ...