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.

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

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

The object, known as 2017 OF201, was found by researchers at the Institute for Advanced Study and Princeton University who were searching for “Planet Nine,” a hypothetical planet larger than ...

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

Scientists hunting for Planet Nine, an elusive planetary body that could change our understanding of the solar system, have ...

As a result of the International Astronomical Union’s 2006 demotion of Pluto from planet to dwarf planet, our solar system ...

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

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

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

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

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