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 ...

At the ragged frontier where the Sun’s influence gives way to the galaxy, a decades‑old spacecraft has stumbled into a ...

"If our solar system is indeed moving this fast, we need to question fundamental assumptions about the large-scale structure of the universe." When you purchase through links on our site, we may earn ...