Where does the solar system end and interstellar space begin? That's a question scientists have been working to answer using ...

Somewhere at the edge of the solar system a new Earth-sized world might be lurking, dubbed Planet Y. Astronomers have long proposed that there might be hidden planets beyond the Kuiper belt, a region ...

Add Yahoo as a preferred source to see more of our stories on Google. When you buy through links on our articles, Future and its syndication partners may earn a commission. Today, the solar system has ...

There have been plenty of attempts to resolve the "Hubble Tension" in cosmology. This feature describes how one of the most important variables in cosmology, the expansion of the universe, takes on ...

The outer solar system once seemed like a quiet backwater. But a glut of tiny, strange moons with unruly orbits are coming into view, revealing hints of a surprising past – and the origin of Saturn's ...