Nearly half a century after it left Earth, a battered spacecraft built with 1970s electronics is closing in on a frontier no ...

A Harvard physicist who sounded the alarm earlier this month about a rare interstellar object passing through our solar system — suggesting it might be more than a comet — now says it could even be a ...

The eyes of every astronomer widened this year when an interstellar traveler was discovered in our solar system. Despite some suggestions that it could be an alien spacecraft, observations from some ...

An interstellar object named 3I/ATLAS, confirmed to be a comet, is passing through Earth's solar system. The comet poses no threat to Earth and will make its closest approach to our planet on Dec. 19.

A small, icy visitor from beyond the solar system is giving scientists an unusually close look at the chemistry that may help ...

A mysterious cigar-shaped object spotted tumbling through our solar system last year may have been an alien spacecraft sent to investigate Earth, astronomers from Harvard University have suggested.

NASA has released new images of the interstellar comet 3I/ATLAS, captured by various ground and space telescopes. Officials also dismissed conspiracy theories that the comet could be extraterrestrial ...

The comet is the third object ever confirmed to have entered our cosmic neighborhood from elsewhere in the galaxy. Space ...

A comet known as 3I/ATLAS made news when it was confirmed to be the 3rd-ever object observed to have originated outside Earth's solar system. Though the object poses no threat to Earth, astronomers ...