OF201 is incredibly lightweight on a cosmic scale. Scientists estimate its mass is about 20,000 times less than Earth’s and ...

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

Almost 20 years after Pluto was infamously downgraded from its status as a planet, scientists now believe they have ...

Jupiter joins Mercury in early twilight as Mars lingers with Leo after dark. Saturn is visible in the morning, meeting ...

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

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

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

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 ...

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

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's outer reaches.