The Guardian - 6/21/13, Michael Hogan
As the MoD releases its final UFO files, here are the world's most famous sightings of alien spaceships – sorry, we mean unidentified flying objects. Keep watching the skies.
4 Kenneth Arnold case, 1947
Pilots EJ Smith, Kenneth Arnold, and Ralph E Stevens look at a photo of a UFO that they spotted in Washington. Photograph: Bettmann/Corbis
The press first coined the term "flying saucer" after this Idaho pilot claimed he had seen a string of nine shiny, saucer-shaped objects flying at supersonic speeds near Mount Rainier, Washington. What's the frequency, Kenneth?
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