Project Blue Book: The U.S. Air Force’s Systematic Study of Unidentified Aerial Phenomena (1952–1969)

To the point

Project Blue Book was the United States Air Force's systematic 1952–1969 study of unidentified aerial phenomena to determine whether they posed a national security threat, guided by Nathan Twining, Edward J. Ruppelt, J. Allen Hynek, and Major Hector Quintanilla, which concluded that most sightings were misidentifications or explainable while no evidence of extraterrestrial technology or threat existed, left some cases unresolved, and ended in 1969 when Secretary Robert Seamans announced there was no threat, after Hynek went on to found CUFOS in 1973.