From the Greys to the Nordics, these aliens appear frequently across abduction stories and science fiction tales.

Avi Loeb, a Harvard astronomer who has made headlines with his theories about alien encounters, will lead a White House ...

The White House has appointed Harvard astronomer Avi Loeb to lead a new scientific advisory team investigating unidentified ...

Harvard astrophysicist Avi Loeb argues 3I/ATLAS and other interstellar objects may hint at alien technology, drawing fame, ...

Scientists may have just taken one of the biggest steps yet in the search for life beyond Earth. Meet K2 18 b, a distant ...

Somewhere in the Mojave Desert, a gleaming white dome sits in the middle of nowhere, and the story behind it is stranger than ...

Scientists say moons around rogue planets wandering through the galaxy could remain warm enough for life thanks to tidal heating and hydrogen-rich atmospheres. These dark, starless worlds may have had ...

A rare visitor from another star system prompted SETI to hunt for alien technology, but the mysterious object appears to be a ...

Scientists propose building a lab on the moon to screen Mars and other space samples for alien microbes before they ever ...

An interstellar comet that blazed past the sun and swung by Earth last year could be nearly three times older than our solar ...