Earth already contains organisms that survive conditions humans could never endure. Alien life, if it exists, may force ...

The United States is stepping back from the most direct test yet of possible alien biology on Mars just as new telescopes and probes are racing ahead to hunt for life light‑years away. Lawmakers have ...

Alien life may not need the kind of home humans instinctively search for. Some of the strangest possibilities begin once ...

Recent observations suggest that scientists have identified potential microbial fingerprints in the atmospheres of other planets, raising intriguing questions about the possibility of alien life ...

Claims that aliens are already here are everywhere, but proving them is another matter. The strongest cases become more ...