17 de Dezembro de 1969.

Project Blue Book: The USAF closes its study of UFOs, stating that sightings were generated as a result of 'A mild form of mass hysteria, Individuals who fabricate such reports to perpetrate a hoax or seek publicity, Psychopathological persons, and Misidentification of various conventional objects'. Project Blue Book was one of a series of systematic studies of Unidentified flying objects (UFOs) conducted by the United States Air Force. It was the second revival of such study, started in 1952, and was active up to January 1970, as it had been ordered for termination in December 1969.

The goal of the project BLUE BOOK was to determine if UFOs were a potential threat to national security. Thousands of UFO reports were collected, analysed and filed. As the result of the Condon Report, Project Blue Book was shut down in 1969. This project was the last publicly known UFO research project led by the USAF. Though many accepted Blue Book's final conclusions that there was nothing extraordinary about UFOs, critics -- then and now -- have charged that Blue Book, especially in its later years, was engaging in dubious research, or even perpetuating a cover up of UFO evidence. Some evidence suggests that not only did some UFO reports bypass Blue Book entirely, but that the U.S. Government continued collecting and studying UFO reports after Blue Book had been discontinued, despite official claims to the contrary.

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