It starts with a signal. Faint, strange, and unlike anything humanity has ever recorded. Within hours, it escalates into an event that changes the course of history as an alien arrival on Earth ...

Experts outline four scenarios for first contact, from detecting radio signals to direct encounters with alien spacecraft. Each possibility would profoundly reshape global politics, science, and ...

There’s no denying the allure of alien artifacts. Science fiction is awash in the material remnants of extraterrestrial civilizations, which surface in everything from the classic books of Arthur C.