From Abracadabra to Zombies
In a nutshell: Some people think flying saucers are spaceships from other planets. Most scientists don't think so.
Some people say that aliens have come to Earth in flying saucers. It's not likely that anyone from another planet has reached Earth in a flying saucer or a flying teacup, for that matter. (See the entry on UFOs for an explanation of why travel between stars is unlikely.) Where did the idea of a flying saucer come from?
On June 24, 1947, Kenneth Arnold claimed that he saw nine "crescent shaped" aircraft flying wildly at very fast speeds near Mount Rainier, Washington. He said they reminded him of saucers skimming over water. An editor of the Eastern Oregonian newspaper wrote that Arnold saw "round" objects. Others wrote that he saw "disc-shaped" objects. Within a few weeks, there were hundreds of reports nationwide of sightings of flying "saucers."
Here's a picture of Mr. Arnold with a drawing of what he thinks he saw. Have you ever played the whisper game, where somebody whispers something in one person's ear who passes it on by whispering in another person's ear? You keep passing it on until you get to the last person in the game. Then that person says what he heard. Usually, what the last person heard is way different from what the first person whispered. Things get jumbled as the message gets passed on. That's what seems to have happened to Arnold's crescents that seemed to look like saucers skimming across water that became round that became discs that became flying saucers.
In the years since Arnold saw his crescent-shaped UFOs, several pranksters have faked photos of flying saucers. It's actually pretty easy to do. See How to fake UFO photos by Almiro Barauna for a lesson.
The Spoof is Out There (This is a story about fake flying saucers and how they can scare people. The story is from The Sun, not one of the more trustworthy sources for anything, but it is still fun.)