Astronomers manning an asteroid warning system caught a glimpse of a large, bright object zipping through the solar system ...

Newfound interstellar object 3I/ATLAS may be carrying pristine material from early in the Milky Way’s star-forming history.

An object dubbed 3I/ATLAS is only the third interloper from outside the Solar System seen in all of human history.

The precursors of heavy elements might arise in the plasma underbellies of swollen stars or in smoldering stellar corpses.

NASA's New Horizons spacecraft has traveled so far from Earth that the relative position of the stars is beginning to shift — a fact that could help future spacecraft navigate the galaxy on their own.