UFO Close Encounters - Full Documentary

An unidentifed fying object, or UFO, in its most general deKnition, is any apparent anomaly in the sky that is not identiKable as a known object or phenomenon. Culturally, UFOs are associated with claims of visitation by extraterrestrial life or government-related conspiracy theories, and have become popular subjects in Kction. While UFOs are often later identiKed, sometimes identiKcation may not be possible owing to the usually low quality of evidence related to UFO sightings (generally anecdotal evidence and eyewitness accounts).
Stories of fantastical celestial apparitions have been told since antiquity, but the term "UFO" (or "UFOB") was ofKcially created in 1953 by the United States Air Force (USAF) to serve as a catch-all for all such reports. In its initial deKnition, the USAF stated that a "UFOB" was "any airborne object which by performance, aerodynamic characteristics, or unusual features, does not conform to any presently known aircraft or missile type, or which cannot be positively identiKed as a familiar object." Accordingly, the term was initially restricted to that fraction of cases which remained unidentiKed after investigation, as the USAF was interested in potential national security reasons and/or "technical aspects" (see Air Force Regulation 200-2).
During the late 1940s and through the 1950s, UFOs were often referred to popularly as "Xying saucers" or "Xying discs". The term UFO became more widespread during the 1950s, at Krst in technical literature, but later in popular use. UFOs garnered considerable interest during the Cold War, an era associated with a heightened concern for national security. Various studies have concluded that the phenomenon does not represent a threat to national security nor does it contain anything worthy of scientiKc pursuit (e.g., 1951 Flying Saucer Working Party, 1953 CIA Robertson Panel, USAF Project Blue Book, Condon Committee).