On 7 November 2006 a group of United Airlines staff at Gate C17 at Chicago O'Hare — mechanics, a supervisor, ramp crew — saw a dark disc hanging motionless above the terminal under a solid overcast. By their account it went up so sharply that it punched a round hole in the cloud, through which blue sky was visible for a couple of minutes. United and the Federal Aviation Administration at first denied receiving any report. After a Freedom of Information request from the Chicago Tribune, a recording surfaced of a controller discussing the sighting with a supervisor. The official explanation is a weather phenomenon. No flights were held, and no investigation followed.

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The Berwyns and the Welsh Roswell

On the evening of 23 January 1974 the ground shook in the Berwyn mountains of north Wales and lights were seen on the hillside. People assumed an aircraft had come down; police, a nurse and mountain rescue climbed in the dark and found nothing. Over the years the story acquired military lorries carrying containers away, and the nickname the Welsh Roswell. Seismic records show a real earthquake of about magnitude 3.5 that evening, and the lights fit well with a bright fireball seen across northern Britain in the same minutes. The coincidence of two events in one evening produced everything else.