Forbes contributors publish independent expert analyses and insights. An award-winning reporter writing about stargazing and the night sky. An object has been discovered orbiting the sun far beyond ...

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, ...

Forbes contributors publish independent expert analyses and insights. An award-winning reporter writing about stargazing and the night sky. The solar system suddenly has a new member. A new object ...

"It is possible that a planet once existed in the solar system but was later ejected, causing the unusual orbits we see today." When you purchase through links on our site, we may earn an affiliate ...

Astronomers are intensifying the search for the hypothetical planet nine, a massive world thought to orbit far beyond Neptune ...

Is there a massive undiscovered planet on the outer reaches of the Solar System? The idea has been around since before the discovery of Pluto in the 1930s. Labelled as planet X, prominent astronomers ...

Astronomers are re-examining distant Kuiper Belt objects for signs of a massive, unseen planet far beyond Neptune. Recent ...

Is there a massive undiscovered planet on the outer reaches of the solar system? The idea has been around since before the discovery of Pluto in the 1930s. Labeled as planet X, prominent astronomers ...

Mike Brown is convinced that beyond Neptune, at the far reaches of our solar system, there's an unseen giant planet. "This is the 5th largest planet in our solar system, lurking out there, waiting to ...