The discovery of 2017 OF201 is significant, as it challenges the hypothesis of Planet Nine, a hypothetical planet thought to ...

In the cold, distant reaches of the Solar System, far beyond Pluto, astronomers have just identified what could be a new ...

At the very edge of our solar system, beyond the grasp of Neptune and even past the icy sprawl of Pluto’s domain, a new ...

Scientists believe such an extreme orbit means the object was pushed and pulled by the gravity of giant planets like Jupiter ...

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 ...

On May 21, the International Astronomical Union’s Minor Planet Center announced the discovery of 2017 OF 201, which, because ...

A small team led by Sihao Cheng, Martin A. and Helen Chooljian Member in the Institute for Advanced Study's School of Natural ...

Researchers say they found a curious dot on infrared images taken 23 years apart that seems to be moving in a manner consistent with a large, distant planet.

Billions of years ago, in the frozen edges of the solar system, a violent impact shaped one of space’s oddest pairs. Instead of a typical planet-moon setup, Pluto and Charon became a binary system.