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 ...

Earth has a new neighbor that lives far, far away. Scientists from the Institute for Advanced Study's School of Natural ...

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's outer reaches.