OF201 spends only 1% of its orbital time close enough to us to be detectable. The presence of this single object suggests ...

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

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

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

A new dwarf planet, discovered beyond Neptune and described as Pluto's 'cousin,' could void the hypothesis of a Planet X in ...

There’s a new object in the distant reaches of our solar system, and it might just offer clues to a long-standing cosmic ...

A team of astronomers believe they may have discovered a new dwarf planet—just like Pluto—on the edge of our solar system.

WASHINGTON: A group of scientists has found a strange new object about 435 miles wide at the far edge of the solar system. It ...

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 ...

It's an evocative idea that has long bedeviled scientists: a huge and mysterious planet is lurking in the darkness at the ...

As explained in a pre-press paper [PDF] titled “Discovery of a dwarf planet candidate in an extremely wide orbit: 2017 OF201” ...

There’s a new frozen oddball orbiting the Sun, and it’s not your average space rock. It’s a planet—a minor one, to be ...