"Coincidentally, in 2006, a UFO was sighted over Chicago's O'Hare International Airport. Unlike the Chinese authorities, the US Federal Aviation Administration declined to conduct an investigation into that incident and airport workers were ordered to refrain from speaking with the media.

According to The Chicago Tribune:

A flying saucerlike object hovered low over O'Hare International Airport for several minutes before bolting through thick clouds with such intense energy that it left an eerie hole in overcast skies, said some United Airlines employees who observed the phenomenon. Was it an alien spaceship? A weather balloon lost in the airspace over the world's second-busiest airport? A top-secret military craft? Or simply a reflection from lights that played a trick on the eyes?

… "To fly 7 million light years to O'Hare and then have to turn around and go home because your gate was occupied is simply unacceptable," said O'Hare controller and union official Craig Burzych.

Renowned astrophysicist Stephen Hawking suggested in April that it's likely aliens exist, given the vastness of the universe, and they're probably hostile.

"We only have to look at ourselves to see how intelligent life might develop into something we wouldn't want to meet. I imagine they might exist in massive ships, having used up all the resources from their home planet. Such advanced aliens would perhaps become nomads, looking to conquer and colonize whatever planets they can reach," he said. "If aliens ever visit us, I think the outcome would be much as when Christopher Columbus first landed in America, which didn't turn out very well for the native Americans."
..."

(From a CSM article on recent UFO sightings in China)

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