Quick, imagine an animal tongue. What came into your mind? The flicking forked tongue of a snake? A cow licking a block of ...

When we imagine alien life, we picture monsters, insects, or tentacles—but what if the most realistic aliens are human-like?

In 1967, astronomers thought they had finally heard from the neighbors. They intercepted a signal so regular and precise it seemed impossible for it to be natural. But the excitement didn’t last.