An unidentified flying object (UFO) is any perceived aerial phenomenon that cannot be immediately identified or explained. Upon investigation, most UFOs are identified as known objects or atmospheric phenomena, while a small number remain unexplained.
UFO conspiracy theories are a subset of conspiracy theories which argue that various governments and politicians globally, in particular the United States Government, are suppressing evidence that unidentified flying objects are controlled by a non-human intelligence or built using alien technology. Such conspiracy theories usually argue that Earth governments are in communication or cooperation with extraterrestrial visitors despite public disclaimers, and further that some of these theories claim that the governments are explicitly allowing alien abduction.
Ufology is the investigation of unidentified flying objects (UFOs) by people who believe that they may be of extraordinary origins. While there are instances of government, private, and fringe science investigations of UFOs, ufology is generally regarded by skeptics and science educators as a canonical example of pseudoscience.
Project Blue Book was the code name for the systematic study of unidentified flying objects by the United States Air Force from March 1952 to its termination on December 17, 1969. The project, headquartered at Wright-Patterson Air Force Base, Ohio, was initially directed by Captain Edward J. Ruppelt and followed projects of a similar nature such as Project Sign established in 1947, and Project Grudge in 1948. Project Blue Book had two goals, namely, to determine if UFOs were a threat to national security, and to scientifically analyze UFO-related data.
The extraterrestrial hypothesis (ETH) proposes that some unidentified flying objects (UFOs) are best explained as being physical spacecraft occupied by extraterrestrial intelligence or non-human aliens, or non-occupied alien probes from other planets visiting Earth.
Josef Allen Hynek was an American astronomer, professor, and ufologist. He is perhaps best remembered for his UFO research. Hynek acted as scientific advisor to UFO studies undertaken by the U.S. Air Force under three projects: Project Sign (1947–1949), Project Grudge (1949–1951) and Project Blue Book (1952–1969).
Stanton Terry Friedman was an American nuclear physicist and professional ufologist who resided in New Brunswick, Canada. He was the original civilian investigator of the Roswell UFO incident.
Jacques Fabrice Vallée is an Internet pioneer, computer scientist, venture capitalist, author, ufologist and astronomer currently residing in San Francisco, California and Paris, France.
The Robertson Panel was a scientific committee which met in January 1953 headed by Howard P. Robertson. The Panel arose from a recommendation to the Intelligence Advisory Committee (IAC) in December 1952 from a Central Intelligence Agency (CIA) review of the U.S. Air Force investigation into unidentified flying objects, Project Blue Book. The CIA review itself was in response to widespread reports of unidentified flying objects, especially in the Washington, D.C. area during the summer of 1952.
Edward James Ruppelt was a United States Air Force officer probably best known for his involvement in Project Blue Book, a formal governmental study of unidentified flying objects (UFOs). He is generally credited with coining the term "unidentified flying object", to replace the terms "flying saucer" and "flying disk" – which had become widely known – because the military thought them to be "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 for short."
James Edward McDonald was an American physicist. He is best known for his research regarding UFOs. McDonald was a senior physicist at the Institute for Atmospheric Physics and a professor of meteorology at the University of Arizona in Tucson.
The Condon Committee was the informal name of the University of Colorado UFO Project, a group funded by the United States Air Force from 1966 to 1968 at the University of Colorado to study unidentified flying objects under the direction of physicist Edward Condon. The result of its work, formally titled Scientific Study of Unidentified Flying Objects, and known as the Condon Report, appeared in 1968.
Project Grudge was a short-lived project by the U.S. Air Force (USAF) to investigate unidentified flying objects (UFOs). Grudge succeeded Project Sign in February, 1949, and was then followed by Project Blue Book. The project formally ended in December 1949, but continued in a minimal capacity until late 1951.
The Mariana UFO incident occurred in August 1950 in Great Falls, Montana. The film footage of the sighting is believed to be among the first ever taken of what came to be called an unidentified flying object. The footage was investigated by the U.S. Air Force, and found to be reflections from two F-94 jet fighters.
Identifying unidentified flying objects (UFOs) is a difficult task due to the normally poor quality of the evidence provided by those who report sighting the unknown object. Observations and subsequent reporting are often made by those untrained in astronomy, atmospheric phenomena, aeronautics, physics, and perception. Nevertheless, most officially investigated UFO sightings, such as from the U.S. Air Force's Project Blue Book, have been identified as being due to honest misidentifications of natural phenomena, aircraft, or other prosaic explanations. In early U.S. Air Force attempts to explain UFO sightings, unexplained sightings routinely numbered over one in five reports. However, in early 1953, right after the CIA's Robertson Panel, percentages of unexplained sightings dropped precipitously, usually being only a few percent in any given year. When Project Blue Book closed down in 1970, only 6% of all cases were classified as being truly unidentified.
From July 12 to 29, 1952, a series of unidentified flying object (UFO) sightings were reported in Washington, D.C., and later became known as the Washington flap, the Washington National Airport Sightings, or the Invasion of Washington. The most publicized sightings took place on consecutive weekends, July 19–20 and July 26–27. UFO historian Curtis Peebles called the incident "the climax of the 1952 (UFO) flap" - "Never before or after did Project Blue Book and the Air Force undergo such a tidal wave of (UFO) reports."
Brian O'Brien was an optical physicist and "the founder of the Air Force Studies Board and its chairman for 12 years. O'Brien received numerous awards, including the Medal for Merit, the nation's highest civilian award, for his work on optics in World War II and the Frederic Ives Medal in 1951. Circa 1966 he "chaired an ad hoc committee under the USAF Science Advisory Board (AFSAB) looking into the UFO problem". He also had steering power over National Academy of Sciences (NAS) projects, Project Blue Book, and helped pave the way for the Condon Committee.
The Advanced Aerospace Threat Identification Program (AATIP) was an unclassified but unpublicized investigatory effort funded by the United States Government to study unidentified flying objects (UFOs) or unexplained aerial phenomena (UAP). The program was first made public on December 16, 2017. The program began in 2007, with funding of $22 million over the five years until the available appropriations were ended in 2012. The program began in the U.S. Defense Intelligence Agency.
The Report on Unidentified Flying Objects is a 1956 book by then-retired Air Force UFO investigator Edward J. Ruppelt, detailing his experience running Project Bluebook. The book was noted for its suggestion that a few UFO sightings might be linked to spikes of atomic radiation. Contemporary media summarized four topics discussed in the book:
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