Astronomers used a telescope in Hawaii to find a new object on the outer edges of our solar system, helping to fuel evidence of a long-standing theory about Planet Nine, or Planet X.

Explore the fascinating motion of our Solar System as it journeys not just around the Sun, but also through the vastness of the Milky Way galaxy and the Universe beyond. This in-depth video unpacks ...

Astronomers have discovered "Ammonite," a mysterious object on the solar system’s edge whose unusual orbit challenges current ...

While astronomers have long searched for a mysterious ninth planet lurking beyond Pluto, a recent discovery is turning that search on its head. Spotted through the powerful Subaru Telescope in Hawaii, ...

This object is the first confirmed body that orbits the sun once for every ten orbits Neptune completes.

A team of astronomers discovered a strange object in the outer solar system that is in a resonant orbit with Neptune.

Astronomers have found 2023 KQ14, nicknamed Ammonite, a rare sednoid with a unique orbit that challenges the Planet Nine ...

A rare celestial object beyond Neptune, 2020 VN40, moves in sync with Neptune, offering new insights into the outer solar system and fueling the search for Planet Nin ...

"We believe that continuing such activities will further expand our horizon in the field of planetary science." ...

Theories about Planet Nine have been swirling for years, but this newly discovery planet might put those theories to bed for good.

An icy object in perfect sync with Neptune reveals new details about planetary migration and unseen bodies far beyond the Kuiper Belt.

Over the past decade, researchers have been puzzling through Pluto’s mysteries. Meanwhile, the New Horizons probe heads for interstellar space.