Elon Musk has turned a long-running joke about being an extraterrestrial into a central part of his public persona, even as he argues that humanity may be the only intelligent life in the universe.

Wondering whether we're alone in the cosmos is almost a rite of passage for human existence. It's a mystery that scientists – and stargazers – have pondered for many years. The Fermi Paradox poses a ...

Humans have created countless inventions that shape our lives in amazing ways. Some are practical, some are revolutionary, and some are simply fascinating. But if aliens suddenly appeared, which ...