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 ...

Scientists say a nearby red dwarf star hosts a planetary lineup that looks like a mirror image of our own solar system, with rocky worlds bookending a pair of gas-rich planets. Around the star LHS ...

HELSINKI — China has published coordinated papers outlining dual missions to the solar system’s edge, suggesting the long-studied project is nearing formal approval. A lead paper on the design and key ...