The massive stratospheric balloon, measuring about 9 feet in diameter and 40 feet long, was launched outside San Luis, Colo., ...

The cosmic wanderer that has fascinated the world since it was found last summer is finally getting ready to say goodbye for ...

If aliens disclose tomorrow, is it 'Arrival''s calm contact, 'Don't Look Up''s denial, or 'Independence Day''s invasion? We break down the real scenarios fans are debating.

A classified response from the CIA has reopened debate around 3I/ATLAS. NASA calls it a comet, but rising speculation ...

Sputnik skies to analysis of interstellar visitors, scientists are rethinking how and where to look for physical traces of ...

An alien comet is slipping away forever. For a few hours only, a livestream will show its final cosmic goodbye.

NASA's plans for Mars sample return are effectively cancelled as part of a bill approved by the U.S. Congress, ending efforts ...

Tune in today (Jan. 16) to bid farewell to interstellar comet 3I/ATLAS, courtesy of a livestream from the Virtual Telescope ...

Interstellar comet 3I/ATLAS is now barreling away from the sun, never to return to the solar system. There's one more chance ...

Astronomers are using China's powerful FAST radio telescope to chase after 100 intriguing signals detected by the SETI@home ...

The search for extraterrestrial life in this vast universe needs all hands on deck. A crowd-sourced project from UC Berkeley ...