The universe is vast and teeming with stars – but if intelligent life exists, it may not be able to visit Earth.

The newest visitor from deep space, interstellar comet 3I/ATLAS, has arrived with a literal pulse that is stirring up talk of alien engineering as much as it is exciting astronomers. As its brightness ...

Every few years, a new “mystery metal” surfaces and the internet races to declare it proof that we are not alone. Shiny shards, polished spheres, and desert monoliths are quickly framed as alien ...

A Pentagon release of new UFO footage has revived the question of whether aliens could realistically travel to Earth.