The celestial body's unusual orbit “implies that something extraordinary occurred" in the early days of the solar system—and ...

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

According to study co-author Dr Fumi Yoshida, Neptune is the only known massive object near the outer Solar System that could ...

A team of astronomers led by the Center for Astrophysics | Harvard & Smithsonian has discovered a rare object far beyond Neptune, from a class known as trans-Neptunian objects, that is moving in ...

Is there a massive undiscovered planet on the outer reaches of the Solar System? The idea has been around since before the ...

A team of astronomers led by the Center for Astrophysics | Harvard & Smithsonian has discovered a rare object far beyond Neptune, from a class known as trans-Neptunian objects, that is moving in ...

Learn more about a sednoid called Ammonite that has been detected in the outer reaches of the Solar System.

A team led by Wang Shiang-yu (王祥宇) and Chen Ying-tung (陳英同) of the Institute of Astronomy and Astrophysics at Academia Sinica ...