Siraj’s Planet Y search started about a year ago when he was trying to find out whether the shape of the Kuiper Belt is flat.

Could a lonely planet wander aimlessly through the restless galaxy change the subtle dance of gravity within our solar system ...

Astronomers have found new evidence, revealing the existence of an unseen and mysterious planet that could be hidden in the solar system. The new research study which is published in the ...

The simulation of the Solar System that came the closest to the observation was the presence of a small planet, between the ...

A mysterious space object named 2023 KQ14, nicknamed “Ammonite,” challenges theories about the mysterious and possible Planet ...

A low-density, puffy planet orbiting relatively far from a young star in a nearly perpendicular orbit. What's going on?

EVANSTON, Ill. — Except for the fact that we call it home, for centuries astronomers didn’t have any particular reason to believe that our solar system was anything special in the universe. But, ...

On August 24, 2006, our solar system lost a planet. It wasn't by cataclysmic destruction, but rather by the vote of the International Astronomical Union, which declared that Pluto, considered the ...

Studying the orbits of thousands of exoplanets shows that large planets tend to have elliptical orbits, while smaller planets tend to have more circular orbits. This split coincides with several other ...

Astronomers are investigating a strange class of exoplanets known as eccentric warm Jupiters — massive gas giants that orbit ...

The search for an unknown planet in our solar system has inspired astronomers for more than a century. Now, a recent study suggests a potential new candidate, which the paper’s authors have dubbed ...