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

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

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.

A recently discovered celestial body is rewriting our knowledge of the Kuiper Belt and maybe challenging the existence of the ...

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

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

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

In 2006, the International Astronomical Union demoted Pluto to one of dozens of dwarf planets. After its discovery in 1930, Pluto was declared the ninth planet in our solar system and quickly ...

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

The universe's vastness challenges human comprehension. It contains trillions of galaxies and countless stars. Pluto's ...