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 ...

There have been questions about a mysterious ninth planet in our solar system for nearly a decade. Pluto was unseated as number nine in 2006. Now, a group of international researchers say they may ...

Astronomers have found new evidence that a mysterious ninth planet may be hiding at the edge of the solar system - rewriting what we know about the cosmos again. An international team from Taiwan, ...

Six planets are about to stack up in the evening sky in a rare alignment that will briefly turn the western horizon into a live solar system diagram. For a short window after sunset, Mercury, Venus, ...

A young star called V1298 Tau is giving astronomers a front-row seat to the birth of the galaxy’s most common planets. Four massive but extremely low-density worlds orbiting the star appear to be ...