So far, humanity has yet to find its first "exomoon"—a moon orbiting a planet outside of the solar system. But that hasn't been for lack of trying. According to a new paper by Thomas Winterhalder of ...

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 ...

Astronomers are closing in on one of the most tantalizing possibilities in planetary science, evidence that a previously unknown world may be lurking in the outer reaches of the solar system. The ...