An unidentified flying object (usually abbreviated to UFO or U.F.O.)is any unusual apparent object in the sky whose cause cannot be identified by the observer, or (in a narrower definition) by investigators; though in popular usage it more loosely means alien spacecraft being one explanation (among several) offered for such sightings. Though UFO sightings have occurred throughout history, modern interest in them dates from World War II, since when governments have investigated UFO reports, often from a military perspective, and UFO researchers have investigated, written about and created organizations devoted to the subject.
Studies have established that the majority of UFOs are observations of some real but conventional object—most commonly aircraft, balloons, noctilucent clouds, nacreous clouds, or astronomical objects such as meteors or bright planets — that have been misidentified by the observer as anomalies, while a small percentage of reported UFOs are hoaxes However, after excluding these incorrect reports, between 5% and 20% of the total remain unexplained, and so can be classified as unidentified in the strictest sense. Many such reports have been made by trained observers such as pilots, police and the military; some involve radar traces, so not all reports are visual.Proponents of an extraterrestrial hypothesis believe that these unidentifiedreports are of alien spacecraft, though various other hypotheses have been proposed.
While UFOs have been the subject of extensive investigation by various governments, and some scientists support the extraterrestrial hypothesis, few scientific papers about UFOs have been published in peer-reviewed journals.There has been some debate in the scientific community about whether any scientific investigation into UFO sightings is warranted
FOs have become a prominent theme in modern culture, and this cultural phenomenon has been the subject of academic research.
UFOs have become a prominent theme in modern culture, and this cultural phenomenon has been the subject of academic research.
To account for unsolved UFO cases, several hypotheses have been proposed.
The extraterrestrial hypothesis (ETH) is defined by Edward U. Condon in the 1968Condon Report as "The idea that some UFOs may be spacecraft sent to Earth from another civilization, or on a planet associated with a more distant star", further attributing the popularity of the idea to Donald Keyhoe's UFO book from 1950, though the idea clearly predated Keyhoe, appearing in newspapers and various government documents.This is probably the most popular theory among Ufologists. Some private or governmental studies, some secret, have concluded in favor of the ETH, or have had members who disagreed with official conclusions against the conclusion by committees and agencies to which they belonged.
The UFO Hostility Hypothesis is inside the extraterrestrial hypothesis. It says that the extraterrestrial beings that travel in the UFOs, or most of them, are hostile. The hypothesis comes because of the Cattle Mutilations and the observations made by Wilhelm Reich amd Jerome Eden during their experiments with the Cloudbuster
The paranormal/occult hypothesis is a variant of the interdimensional hypothesis, invoked to explain so-called paranormal aspects sometimes associated with UFO reports.
The psychosocial hypothesis, that what people report as UFO experiences is the result of psychological misperception mechanisms and is strongly influenced by popular culture.
The earthquake lights/tectonic strain hypothesis: UFOs are caused by strains in Earth's crust near earthquake faults, which can also supposedly induce hallucinations
.That UFOs are military flying saucers, top secret or experimental aircraft unfamiliar to most people.
Attempts have been made to reverse engineer the possible physics behind UFOs through analysis of both eyewitness reports and the physical evidence, on the assumption that they are powered vehicles. Examples are former NASA and nuclear engineer James McCampbell in his book Ufology, NACA/NASA engineer Paul R. Hill in his book Unconventional Flying Objects, and German rocketry pioneer Hermann Oberth. Among subjects tackled by McCampbell, Hill, and Oberth was the question of how UFOs can fly at supersonic speeds without creating a sonic boom. McCampbell's proposed solution is microwave plasmaparting the air in front of the craft. In contrast, Hill and Oberth believed UFOs utilize an as yet unknown anti-gravity field to accomplish the same thing as well as provide propulsion and protection of occupants from the effects of high acceleration.
Radar contact and tracking, sometimes from multiple sites. These have included military personnel and control tower operators, simultaneous visual sightings, and aircraft intercepts. One such recent example were the mass sightings of large, silent, low-flyingblack triangles in 1989 and 1990 over Belgium, tracked by NATO radar and jet interceptors, and investigated by Belgium's military (included photographic evidence).Another famous case from 1986 was the JAL 1628 case over Alaska investigated by theFAA.
Photographic evidence, including still photos, movie film, and video.
Claims of physical trace of landing UFOs, including ground impressions, burned and/or desiccated soil, burned and broken foliage, magnetic anomalies[specify], increased radiation levels, and metallic traces. See, e. g. Height 611 UFO Incident or the 1964Lonnie Zamora's Socorro, New Mexico encounter of the USAF Project Blue Bookcases). A well-known example from December 1980 was the USAF Rendlesham Forest Incident in England. Another occurred in January 1981 in Trans-en-Provence and was investigated by GEPAN, then France's official government UFO-investigation agency.Project Blue Book head Edward J. Ruppelt described a classic 1952 CE2 case involving a patch of charred grass roots.
Physiological effects on people and animals including temporary paralysis, skin burns and rashes, corneal burns, and symptoms superficially resembling radiation poisoning, such as the Cash-Landrum incident in 1980.
Animal/cattle mutilation cases, that some feel are also part of the UFO phenomenon
.Biological effects on plants such as increased or decreased growth, germination effects on seeds, and blown-out stem nodes (usually associated with physical trace cases or crop circles)
Electromagnetic interference (EM) effects. A famous 1976 military case over Tehran, recorded in CIA and DIA classified documents, was associated with communication losses in multiple aircraft and weapons system failure in an F-4 Phantom II jet interceptor as it was about to fire a missile on one of the UFOs.
Apparent remote radiation detection, some noted in FBI and CIA documents occurring over government nuclear installations at Los Alamos National Laboratory and Oak Ridge National Laboratory in 1950, also reported by Project Blue Book director Ed Ruppelt in his book.
Claimed artifacts of UFOs themselves, such as 1957, Ubatuba, Brazil, magnesiumfragments analyzed by the Brazilian government and in the Condon Report and by others. The 1964 Socorro/Lonnie Zamora incident also left metal traces, analyzed byNASA. A more recent example involves "the Bob White object" a tear drop shaped object recovered by Bob White and was featured in the TV show UFO Hunters.
Angel hair and angel grass, possibly explained in some cases as nests from ballooning spiders or chaff.