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

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 ...

Astronomers have discovered a new member of a rare and mysterious class of solar system objects known as sednoids - a subset of extreme trans-Neptunian objects (ETNOs) with exceptionally distant, ...

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 ...

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

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

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

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

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

"It is possible that a planet once existed in the solar system but was later ejected, causing the unusual orbits we see today ...

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 ...