A possible new dwarf planet has been discovered at the edge of our solar system, so far-flung that it takes around 25,000 ...

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.

The object’s aphelion—the farthest point on the orbit from the sun—is more than 1,600 times that of Earth’s orbit,” Institute ...

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 ...

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

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

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 ...

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

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