Happy 60th anniversary to the flying saucer:
1947: Pilot Kenneth Arnold sights a series of unidentified flying objects near Washington's Mt. Rainier. It's the first widely reported UFO sighting in the United States, and, thanks to Arnold's description of what he saw, leads the press to coin the term flying saucer.
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Whether Arnold actually saw something or not, the resulting publicity touched off a worldwide spate of UFO sightings. Barely two weeks after Arnold's flight, the Roswell story broke, and UFO hysteria was on.
Was it the power of suggestion that led to all these sightings, or was 1947 a peak travel year for little green men? You decide.
I vote for the latter. I'm sure they wanted to keep visiting, but events conspired to prevent it. First, their planet was devastated by global warming, then fuel costs became so high that they had to choose between food and medicine or visiting Earth. Finally, a Democrat was elected supreme president of the planet, and conditions improved so dramatically that no one could imagine the point of leaving the planet ever again.