Did the idea of UFOs begin with one single event?

Before the term UFO became widely known, there was the famous 1947 sighting by pilot Kenneth Arnold. Interestingly, Arnold never described the objects as “flying saucers”—he said they moved like a saucer skipping across water. Newspapers picked up the phrase, and the term “flying saucer” spread across the world. That one report helped shape decades of speculation, government investigations, movies, and conspiracy theories. Eventually, the U.S. Air Force adopted the term Unidentified Flying Ob...