Add Yahoo as a preferred source to see more of our stories on Google. But now a fourth and much larger object has been spotted entering the solar system, and the scientific community is rushing to ...

As it crossed our Solar System, the interstellar object 3I/ATLAS released up to the equivalent of 70 Olympic swimming pools ...

A comet born around another star is carrying water unlike anything ever measured in our solar system. Interstellar comet ...

Learn more about the interstellar traveler, Comet 3I/ATLAS, and what researchers know about its place of origin.

There may be another world lurking between the orbital lines of our solar system. Astronomers in Japan have published their theory of an “Earth-like planet,” dubbed Planet Nine, that’s hiding in plain ...