This is only the third time that a celestial body from outside the solar system has been discovered. Months remain for the ...

Astronomers have announced the discovery of a monumental interstellar object, designated 3I/Atlas, believed to be the largest ...

Astronomers have discovered an interstellar object travelling through the solar system that is expected to pass by Earth ...

A mysterious visitor from another solar system could be an alien spacecraft, according to a leading Harvard astronomer.