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

Tucson's Planetary Science Institute contributes to tracking mystery space objects that help reveal secrets of the solar ...

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

Astronomers have made an extraordinary discovery at the outer edge of our solar system—a strange space rock that dances in ...

Discovered through the Formation of the Outer Solar System: An Icy Legacy (FOSSIL) survey using the Subaru Telescope in ...

The trans-Neptunian object Arrokoth, also known as Ultima Thule, which NASA's space probe New Horizons passed on New Year's Day 2019, may have changed its shape significantly in the first 100 ...

Trans-Neptunian objects (TNO) are some of our solar system's lesser-known objects. They number in the thousands, and they get their name from their orbits. These dwarf planets orbit the sun at a ...

A team of astronomers led by the Center for Astrophysics | Harvard & Smithsonian has discovered a rare object far beyond ...

An oddly tilted object beyond Neptune moves in perfect sync, one orbit for every ten of Neptune’s, and scientists are ...

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

The long-serving space telescope saw the third interloper to enter the solar system from beyond its limits late on Monday ...

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