Researchers found the object named 2017 OF201 while searching for "Planet Nine" - a hypothetical planet thought to exist ...

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.

James Webb Space Telescope observations suggest Pluto’s atmosphere is unlike any other in the solar system, confirming a 2017 ...

A sweeping new ICE operation shows how Donald Trump’s focus on immigration is reshaping federal law enforcement.

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

The TNO, which are described as minor planets that orbit the sun at a greater distance than Neptune, were found on the edge ...

Scientists have identified an object about 435 miles (700 km) wide inhabiting the frigid outer reaches of our solar system that might qualify as a dwarf planet, spotting it as it travels on a highly ...

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

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

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

Since its discovery in 1930, Pluto was well-known as the ninth planet in the solar system, far beyond Neptune ... declared that the faraway orb was a dwarf planet due to its location, known ...

The International Astronomical Union reclassified Pluto as a dwarf planet because it does not ... with its icy surface and distant orbit beyond Neptune. But in 2006, Pluto’s planetary reign ...