In the 1930s, televisions weren’t yet commercially available. Instead, American families gathered around their radios to hear news, music, and shows. On the night before Halloween in 1938, a shocking news story hit the airwaves. The bulletin warned that Martians had invaded Earth! Many people panicked . . . until they discovered the announcement wasn’t real. It was a radio play based on The War of the Worlds by novelist H.G. Wells.
Ever since the book came out more than 125 years ago, people have been fascinated by the idea of aliens visiting Earth. Scientists, though, have yet to detect any life on other planets—in our solar system or beyond. For decades, astronomers have listened for radio signals sent by intelligent beings trying to communicate with us. But so far, they haven’t received any messages. That could mean extraterrestrials don’t exist. Or they do exist but don’t have technology advanced enough to chat long distance—let alone to travel across the vastness of space to visit in person.