From the files of Project Blue Book. This event was more extensively detailed in its investigation than others, and the conclusion was that it was a common airplane.
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UFO Database
From the files of Project Blue Book. This incident occurred during an Ohio State home football game and could be viewed from the stadium. The object had multiple witnesses, whose accounts are in the pages below. The object was thought to be a balloon, but was never positively identified.
For more incidents around the world, visit the following links.
UFO Database
Mutual UFO Network
National UFO Reporting Center