An unidentified flying object (UFO), or unidentified anomalous phenomenon (UAP)[a], is any perceived airborne, submerged or transmedium phenomenon that cannot be immediately identified or explained.[2] Upon investigation, most UFOs are identified as known objects or atmospheric phenomena, while a small number remain unexplained.
Duration: 35 seconds.0:35Subtitles available.CC”GIMBAL” Pentagon UFO video, January 2015
While unusual sightings have been reported in the sky throughout history, UFOs became culturally prominent after World War II, escalating during the Space Age. Studies and investigations into UFO reports conducted by governments (such as Project Blue Book in the United States and Project Condign in the United Kingdom), as well as by organisations and individuals have occurred over the years without confirmation of the fantastical claims of small but vocal groups of ufologists who favour unconventional or pseudoscientific hypotheses, often claiming that UFOs are evidence of extraterrestrial intelligence, technologically advanced cryptids, demons, interdimensional contact or future time travelers. After decades of promotion of such ideas by believers and in popular media, the kind of evidence required to solidly support such claims has not been forthcoming. Scientists and skeptic organizations such as the Committee for Skeptical Inquiry have provided prosaic explanations for UFOs, namely that they are caused by natural phenomena, human technology, delusions, and hoaxes. Beliefs surrounding UFOs have inspired parts of new religions even as social scientists have identified the ongoing interest and storytelling surrounding UFOs as a modern example of folklore and mythology understandable with psychosocial explanations.
The U.S. government currently has two entities dedicated to UFO data collection and analysis: NASA’s UAP independent study team and the All-domain Anomaly Resolution Office.
Terminology
During the late 1940s and through the 1950s, UFOs were often called “flying saucers” or “flying discs” based on reporting of the Kenneth Arnold incident.[3] “Unidentified flying object” (UFO) has been in-use since 1947.[4] The acronym, “UFO” was coined by Captain Edward J. Ruppelt, for the USAF. He wrote, “Obviously the term ‘flying saucer’ is misleading when applied to objects of every conceivable shape and performance. For this reason the military prefers the more general, if less colorful, name: unidentified flying objects. UFO”.[5] The term UFO became widespread during the 1950s, at first in technical literature, but later in popular use.[6][7] Unidentified aerial phenomena” (UAP) first appeared in the late 1960s. UAP has seen increasing usage in the 21st century due to negative cultural associations with “UFO”.[4] UAP is sometimes expanded as “unidentified anomalous phenomenon”.[8][9]
While technically a UFO refers to any unidentified flying object, in modern popular culture the term UFO has generally become synonymous with alien spacecraft.[10]The term “extra-terrestrial vehicle” (ETV) is sometimes used to separate this explanation of UFOs from totally earthbound explanations.[11]
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