On June 24, 1947, a private pilot named Kenneth Arnold was flying his small plane over the Cascade Mountains of Washington State, helping search for a missing military aircraft. The sky was bright blue. Then, near Mount Rainier, he saw something he could not explain - nine shiny objects flying in a long line, dipping and weaving between the peaks at incredible speed. He timed them between two mountains and figured they were moving at over 1,200 miles per hour, far faster than any plane in 1947.
When Arnold landed, he told a reporter the objects moved "like a saucer skipping across water." The reporter wrote up the story using the words "flying saucer" - and the phrase shot around the world. Within weeks, newspapers across America were getting calls from people who said they had seen flying saucers too. The U.S. Air Force started a secret program called Project Blue Book to investigate. Over the next 22 years, they collected more than 12,000 reports. Most turned out to be airplanes, weather balloons, the planet Venus, or weird-shaped clouds. A few hundred were never explained.
Kenneth Arnold himself stayed pretty calm about the whole thing. He kept flying his plane and selling fire-fighting equipment and never claimed the saucers were aliens - he thought they might be secret military test planes. But his sighting kicked off the modern UFO craze, inspired hundreds of movies and TV shows, and changed how people look at the sky. Today scientists at NASA and the U.S. military still study "unidentified aerial phenomena." The mystery, like the nine shining objects over Mount Rainier, has never quite gone away.
