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Unidentified Flying Object

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Unidentified flying object



 
 
An unidentified flying object (commonly abbreviated as UFO) is any aerial phenomenon
Phenomenon

A phenomenon is any observation occurrence. In popular usage, a phenomenon often refers to an extraordinary event. In physics, a phenomenon may be a feature of matter, energy, or spacetime....
 whose cause can not be easily or immediately determined. Both military and civilian research show that a significant majority of UFO sightings are identified after further investigation, either explicitly or indirectly (through the presence of clear and simple explanatory factors: see Occam's Razor
Occam's razor

Occam's razor, also Ockham's razor, is a principle attributed to the 14th-century English logician and Franciscan friar, William of Ockham....
. The United States Air Force, who coined the term in 1952, initially defined UFOs as those objects which remain unidentified after scrutiny by expert investigators, though the term UFO is often used more generally to describe any sighting unidentifiable to the reporting observer(s).






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Encyclopedia


An unidentified flying object (commonly abbreviated as UFO) is any aerial phenomenon
Phenomenon

A phenomenon is any observation occurrence. In popular usage, a phenomenon often refers to an extraordinary event. In physics, a phenomenon may be a feature of matter, energy, or spacetime....
 whose cause can not be easily or immediately determined. Both military and civilian research show that a significant majority of UFO sightings are identified after further investigation, either explicitly or indirectly (through the presence of clear and simple explanatory factors: see Occam's Razor
Occam's razor

Occam's razor, also Ockham's razor, is a principle attributed to the 14th-century English logician and Franciscan friar, William of Ockham....
. The United States Air Force, who coined the term in 1952, initially defined UFOs as those objects which remain unidentified after scrutiny by expert investigators, though the term UFO is often used more generally to describe any sighting unidentifiable to the reporting observer(s). Popular culture frequently takes the term UFO as a synonym
Synonym

Synonyms are different words with identical or very similar meanings. Words that are synonyms are said to be synonymous, and the state of being a synonym is called synonymy....
 for alien spacecraft
Extraterrestrial hypothesis

The extraterrestrial hypothesis is the hypothesis that some unidentified flying objects are best explained as being extraterrestrial life or space aliens from extrasolar planets occupying physical spacecraft visiting Earth....
. Some investigators now prefer to use the broader term Unidentified Aerial Phenomenon (or UAP), to avoid the confusion and speculative associations that have become attached to UFO.

Studies have established that only a small percentage of reported UFOs are actual hoaxes, while the majority are observations of some real but conventional object - most commonly aircraft, balloons, or astronomical objects such as meteors or bright planets - which have been misidentified by the observer as anomalies. A small percentage of reported sightings (usually 5%-20%) are classified as unidentified flying objects in the strictest sense. (see below for some studies)

The first reports and official investigations of UFOs began during World War II
World War II

World War II, or the Second World War , was a global military conflict which involved a Participants in World War II, including all of the great powers, organised into two opposing military alliances: the Allies of World War II and the Axis powers....
 with sightings of so-called foo fighter
Foo fighter

The term foo fighter was used by Allies aircraft aircraft pilot in World War II to describe various unidentified flying object or mysterious aerial phenomena seen in the skies over both the European Theater of Operations and Pacific Theater of Operations....
s by Allied
Allies of World War II

The Allies of World War II were the countries officially opposed to the Axis powers of World War II during the World War II. Within the ranks of the Allies powers, the British Empire, the Soviet Union, and the United States of America were known as "The Big Three"....
 airplane crews, and with widespread sightings of European "ghost rockets
Ghost rockets

Ghost Rockets were mysterious rocket- or missile-shaped unidentified flying objects sighted in 1946, mostly in Sweden and nearby countries.About 2000 ghost rockets sightings were logged between May and December 1946, with peaks on the 9 and 11 August 1946....
" in 1946. UFO reports became more common after the first widely publicized US sighting - reported by private pilot Kenneth Arnold
Kenneth Arnold

Kenneth A. Arnold was an American businessman and pilot.He is best-known for making what is generally considered the first widely reported unidentified flying object sighting in the United States, after claiming to see nine unusual objects flying in a chain near Mount Rainier, Washington on June 24, 1947....
 in 1947 - which gave rise to the popular terms "flying saucer" and "flying disc". Since then, millions of people believe that they have seen UFOs, and tens of thousands of such reports have been catalogued.

History

Nuremberg Apr 14 1561
Unexplained aerial observations have been reported throughout history. Some were undoubtedly astronomical in nature: comet
Comet

A comet is a Small Solar System body that orbits the Sun and, when close enough to the Sun, exhibits a visible coma or a tail?both primarily from the effects of solar radiation upon the Comet nucleus....
s, bright meteor
METEOR

METEOR is a Metrics for the evaluation of machine translation output. The metric is based on the harmonic mean of unigram precision and recall, with recall weighted higher than precision....
s, one or more of the five planets which can be seen with the naked eye, planetary conjunctions, or atmospheric optical phenomena
Optical phenomenon

An optical phenomenon is any observable event which results from the interaction of light and matter. See also list of optical topics and optics....
 such as parhelia and lenticular cloud
Lenticular cloud

Lenticular clouds are stationary lens-shaped clouds that form at high altitudes, normally aligned at right-angles to the wind direction. Lenticular clouds can be separated into altocumulus standing lenticularis , stratocumulus standing lenticular , and cirrocumulus standing lenticular ....
s. An example is Halley's Comet, which was recorded first by Chinese astronomers in 240 B.C. and possibly as early as 467 B.C.

Other historical reports seem to defy prosaic explanation, but assessing such accounts is difficult. Whatever their actual cause, such sightings throughout history were often treated as supernatural
Supernatural

The term supernatural or supranatural pertains to an order of existence beyond the scientifically visible universe. Religious miracles are typically supernatural claims, as are Spell and curses, divination, the belief that there is an afterlife for the dead, and innumerable others....
 portents, angel
Ángel

?ngel is the third single from Belinda Peregr?n's debut album: Belinda. It was a massive hit in Mexico and an international hit for Belinda....
s, or other religious omen
Omen

An omen is a phenomenon that is believed to foretell the future, often signifying the advent of change. Omens may be considered "good" or "bad", but the term is more often used in a foreboding sense, as with the word "ominous"....
s. Some objects in medieval paintings seem strikingly similar to UFO reports.Art historians explain those objects as religious symbols, often represented in many other paintings of Middle-Age and Renaissance.

Shen Kuo
Shen Kuo

Shen Kuo or Shen Kua , Chinese style name Cunzhong and Chinese style name#H?o Mengqi Weng, was a polymathic China History of science and technology in China and statesman of the Song Dynasty ....
 (1031–1095), a Song Chinese
Song Dynasty

The Song Dynasty was a ruling Chinese dynasty in China between 960–1279 AD; it succeeded the Five Dynasties and Ten Kingdoms Period, and was followed by the Yuan Dynasty....
 government scholar-official and prolific polymath inventor and scholar, wrote a vivid passage in his Dream Pool Essays
Dream Pool Essays

The Dream Pool Essays was an extensive book written by the polymath Chinese scientist and statesman Shen Kuo by 1088 AD, during the Song Dynasty of China....
 (1088) about an unidentified flying object. He recorded the testimony of eyewitnesses in 11th century Anhui
Anhui

Anhui is a province of China of the People's Republic of China. Located in eastern China across the basins of the Yangtze River and the Huaihe River, it borders Jiangsu to the east, Zhejiang to the southeast, Jiangxi to the south, Hubei to the southwest, Henan to the northwest, and Shandong for a tiny section in the north....
 and Jiangsu
Jiangsu

is a Province of China of the People's Republic of China, located along the east coast of the country. The name comes from jiang, short for the city of Jiangning , and su, for the city of Suzhou....
 (especially in the city of Yangzhou
Yangzhou

Yangzhou is a prefecture-level city in central Jiangsu province of China, People's Republic of China. Sitting on the northern bank of the Yangtze River, it borders the provincial capital of Nanjing to the southwest, Huai'an to the north, Yancheng to the northeast, Taizhou, Jiangsu to the east, and Zhenjiang across the river to the south....
), who stated that a flying object with opening doors would shine a blinding light from its interior (from an object shaped like a pearl) that would cast shadows from trees for ten miles
Li (unit)

The li is a Chinese units of measurement of distance, which has varied considerably over time but now has a standardized length of 500 meters or half a kilometer ....
 in radius, and was able to take off at tremendous speeds.

Early modern reports

Before the terms "flying saucer" were coined in 1947 and "UFO" in 1952, there were a number of reports of unidentified aerial phenomena. These reports date from the mid-nineteenth to early twentieth century. They include:

  • On January 25, 1878, The Denison
    Denison, Texas

    Denison is a city in Grayson County, Texas, Texas, United States. The city's estimated population as of 2007 was 24,103. It is one of two principal cities in the Sherman-Denison Metropolitan Statistical Area....
     Daily News
    wrote that local farmer John Martin had reported seeing a large, dark, circular flying object resembling a balloon flying "at wonderful speed." Martin also said it appeared to be about the size of a saucer, the first known use of the word "saucer" in association with a UFO.
  • On November 17, 1882, a UFO was observed by astronomer
    Astronomer

    An astronomer is a scientist who studies Celestial body such as planets, stars, and Galaxy.Historically, astronomy was more concerned with the classification and description of phenomena in the sky, while astrophysics attempted to explain these phenomena and the differences between them using physical laws....
     Edward Walter Maunder
    Edward Walter Maunder

    Edward Walter Maunder was an English astronomer best remembered for his study of sunspots and the solar magnetic cycle that led to his identification of the period from 1645 to 1715 that is now known as the Maunder Minimum....
     of the Greenwich Royal Observatory and some other European astronomers. Maunder in The Observatory
    The Observatory (astronomy)

    The Observatory is a publication, variously described as a journal, a magazine and a review, devoted to astronomy. It has appeared regularly since 1877, and is currently published every two months....
     reported "a strange celestial
    Celestial

    The term celestial refers to the sky and/or Heaven. An astronomical object is sometimes referred to as a celestial body or celestial object....
     visitor" that was "disc-shaped", "torpedo
    Torpedo

    Note: Prior to 1900, in naval usage "torpedo" could also refer to what today is called a naval mine. For that usage, see naval mine.The modern torpedo is a self-propelled explosive projectile weapon, launched above or below the water surface, propelled underwater toward a target, and designed to detonate on contact or in proximity t...
    -shaped", "spindle
    Spindle (furniture)

    A Spindle, in furniture, is an rotational symmetry shaft, usually made of wood. A spindle is usually made of a single piece of wood and typically has decoration fashioned by hand or with a lathe....
    -shaped", or "just like a Zeppelin
    Zeppelin

    For the English rock group, please see Led Zeppelin. For other meanings please see Zeppelin .A Zeppelin is a type of rigid airship pioneered by the German Count Ferdinand von Zeppelin in the early 20th century, based on designs he had outlined in 1874, designs he had detailed in 1893, and that were reviewed by committee in 1894, which h...
    " dirigible
    Airship

    An airship or dirigible is a aerostat that can be steered and propelled through the air using rudders and propellers or other thrust. Unlike other aerodynamics aircraft such as fixed-wing aircraft and helicopters, which produce lift by moving a wing, or airfoil, through the air, aerostatic aircraft, such as airships and Balloon , stay...
     (as he described it in 1916). It moved rapidly from horizon to horizon. The sighting was during high auroral
    Aurora (astronomy)

    Auroras, sometimes called the northern and southern lights or aurorae , are natural light displays in the sky, usually observed at night sky, particularly in the Geographical pole....
     activity; therefore Maunder assumed it was some extraordinary auroral phenomenon never before seen and called it an "auroral beam".
  • On February 28, 1904, there was a sighting by three crew members on the USS Supply
    USS Supply (1873)

    USS Supply, ex-Illinois , was a schooner-rigged iron steamboat built in 1873 by William Cramp and Sons of Philadelphia, Pennsylvania. Illinois was purchased by the Navy Department from the International Navigation Company on 30 April 1898 for $325,000.00 and commissioned as Supply, Lt....
     300 miles west of San Francisco, reported by Lt. Frank Schofield
    Frank Herman Schofield

    Frank Herman Schofield, born on 4 January 1869 at Jerusalem, New York, was a decorated admiral in the United States Navy, where he served with distinction in the Spanish-American War and World War I....
    , later to become Commander-in-Chief
    Commander-in-Chief

    A commander-in-chief is the commander of a nation's military forces or significant element of those forces. In the latter case, the force element may be defined as those forces within a particular region or those forces which are associated by function....
     of the Pacific Battle Fleet
    Battle Fleet

    The United States Battle Fleet or Battle Force was part of the organization of the United States Navy from 1922 to 1941.The General Order of 6 December 1922 organized the United States Fleet, with the Battle Fleet as the Pacific presence....
    . Schofield wrote of three bright red egg-shaped and circular objects flying in echelon formation
    Echelon formation

    An echelon formation is a military formation in which members are arranged diagonally. Each member is stationed behind and to the right , or behind and to the left , of the member ahead....
     that approached beneath the cloud layer, then changed course and "soared" above the clouds, departing directly away from the earth after two to three minutes. The largest had an apparent size of about six suns.
  • 1916 and 1926: the three oldest known pilot UFO sightings, of 1305 cataloged by . On January 31, 1916, a UK pilot near Rochford
    Rochford

    Rochford is a small town in the Rochford of Essex in the East of England. It is sited about 43 miles from Central London and approximately 21 miles from the Essex county town, Chelmsford....
     reported a row of lights, like lighted windows on a railway carriage, that rose and disappeared. In January 1926, a pilot reported six "flying manhole covers" between Wichita, Kansas
    Wichita, Kansas

    Wichita , is the most populous city in the U.S. state of Kansas, and the county seat of Sedgwick County, Kansas. The 2006 estimated population of 361,420 makes it the 51st largest city in the U.S....
     and Colorado Springs, Colorado
    Colorado Springs, Colorado

    Colorado Springs is a Colorado municipalities#Home Rule Municipality that is the county seat and most populous city of El Paso County, Colorado, Colorado, United States....
    . In late September 1926, an airmail pilot over Nevada
    Nevada

    Nevada is a U.S. state located in the Western United States of the United States of America. The capital is Carson City and the largest city is Las Vegas, Nevada....
     was forced to land by a huge, wingless cylindrical object.
  • On August 5, 1926, while traveling in the Humboldt Mountains
    Kunlun Mountains

    The Kunlun Mountains is one of the longest mountain chains in Asia, extending more than 3,000 km.The Kunlun runs westwards along the northern part of the Tibetan plateau to form the border range of northern Tibet....
     of Tibet
    Tibet

    Tibet is a Tibetan Plateau in Asia, north of the Himalayas, and the home to the indigenous Tibetan people and its related ethnic groups. With an average elevation of 4,900 metres , it is the highest region on Earth and has in recent decades increasingly been referred to as the "Roof of the World"....
    's Kokonor
    Qinghai

    is a provinces of China of the People's Republic of China, named after Qinghai Lake. It borders Gansu on the northeast, the Xinjiang on the northwest, Sichuan on the southeast, and Tibet Autonomous Region on the southwest....
     region, Nicholas Roerich
    Nicholas Roerich

    Nicholas Roerich, also known as Nikolai Konstantinovich Rerikh , was a Russian Painting, philosopher and Theosophy. He was the father of Tibetologist George de Roerich and artist Svetoslav Roerich ....
     reported that members of his expedition saw "something big and shiny reflecting sun, like a huge oval moving at great speed".
  • In the Pacific and European theatres during World War II
    World War II

    World War II, or the Second World War , was a global military conflict which involved a Participants in World War II, including all of the great powers, organised into two opposing military alliances: the Allies of World War II and the Axis powers....
    , "Foo-fighters
    Foo fighter

    The term foo fighter was used by Allies aircraft aircraft pilot in World War II to describe various unidentified flying object or mysterious aerial phenomena seen in the skies over both the European Theater of Operations and Pacific Theater of Operations....
    " (metallic spheres, balls of light and other shapes that followed aircraft) were reported and on occasion photographed by Allied and Axis pilots but were dismissed by scientists as St. Elmo's Fire
    St. Elmo's fire

    St. Elmo's fire is an electricity weather phenomenon in which luminous Plasma is created by a coronal discharge originating from a Ground in an atmospheric electric field ....
     or illusions.
  • On February 25, 1942, the U.S. Army detected a unidentified aircraft both visually and on radar over the Los Angeles
    Los Angeles, California

    Los Angeles is the largest city in the U.S. state of California and the List of United States cities by population in the United States. Often abbreviated as L.A. and nicknamed The City of Angels, Los Angeles is rated as a beta global city, has an estimated population of 3.8 million and spans over in Southern California....
    , California
    California

    California is a U.S. state on the West Coast of the United States of the United States, along the Pacific Ocean. It is bordered by Oregon to the north, Nevada to the east, Arizona to the southeast, and to the south the Mexico state of Baja California....
     region. No readily apparent explanation was offered. The incident later became known as the Battle of Los Angeles
    Battle of Los Ángeles

    The Battle of Los ?ngeles was a military action fought on March 22, 1880 between the Chilean and Peruvian armies during the Tacna and Arica Campaign of the War of the Pacific....
    , or the West coast air raid.
  • In 1946, there were over 2000 reports of unidentified aircraft in the Scandinavian nations, along with isolated reports from France, Portugal, Italy and Greece, then referred to as "Russian hail", and later as "ghost rockets
    Ghost rockets

    Ghost Rockets were mysterious rocket- or missile-shaped unidentified flying objects sighted in 1946, mostly in Sweden and nearby countries.About 2000 ghost rockets sightings were logged between May and December 1946, with peaks on the 9 and 11 August 1946....
    ", because it was thought that these mysterious objects were Russian tests of captured German V1
    V-1 flying bomb

    The Fieseler Fi 103, better known as V-1...
     or V2
    V-2 rocket

    The V-2 rocket was the first ballistic missile and first man-made object to achieve sub-orbital spaceflight, the progenitor of all modern rockets....
     rocket
    Rocket

    A rocket or rocket vehicle is a missile, aircraft or other vehicle which obtains thrust by the Reaction of the rocket to the ejection of fast moving fluid exhaust from a rocket engine....
    s. Over 200 were tracked on radar and deemed to be "real physical objects" by the Swedish military.


The Kenneth Arnold sightings

Arnold Aaf Drawing
The post World War II UFO phase in the United States began with a famous sighting by American businessman Kenneth Arnold
Kenneth Arnold

Kenneth A. Arnold was an American businessman and pilot.He is best-known for making what is generally considered the first widely reported unidentified flying object sighting in the United States, after claiming to see nine unusual objects flying in a chain near Mount Rainier, Washington on June 24, 1947....
 on June 24, 1947 while flying his private plane near Mount Rainier
Mount Rainier

Mount Rainier is an activestratovolcano in Pierce County, Washington, located southeast of Seattle, Washington, Washington, in the United States....
, Washington
Washington

Washington is a U.S. state in the Pacific Northwest region of the United States. Washington was carved out of the western part of Washington Territory which had been ceded by Britain in 1846 by the Oregon Treaty as settlement of the Oregon Boundary Dispute....
. He reported seeing nine brilliantly bright objects flying across the face of Rainier.

Arnold Crescent 1947
Although there were other 1947 U.S. sightings of similar objects that preceded this, it was Arnold's sighting that first received significant media attention and captured the public's imagination. Arnold described what he saw as being "flat like a pie pan", "shaped like saucers and were so thin I could barely see them...", "half-moon shaped, oval in front and convex in the rear. ...they looked like a big flat disk" (see Arnold's drawing at right), and flew "like a saucer would if you skipped it across the water". (One of the objects, however, he would describe later as being almost crescent-shaped, as shown in illustration at left.) Arnold’s descriptions were widely reported and within a few days gave rise to the terms flying saucer and flying disk. Arnold’s sighting was followed in the next few weeks by hundreds of other reported sightings, mostly in the U.S., but in other countries as well.

After reports of the Arnold sighting hit the media, other cases began to be reported in increasing numbers. In one instance a United Airlines
United Airlines

United Air Lines, Inc., trading as United Airlines , is a major carrier of the United States. It is a subsidiary of UAL Corporation with corporate offices in Chicago at 77 West Wacker Drive, and its operations base in nearby Elk Grove Village, Illinois....
 crew sighting of nine more disc-like objects over Idaho
Idaho

The State of Idaho is a U.S. state in the Pacific Northwest region of the United States of America. The state's largest city and Capital is Boise, Idaho....
 on the evening of July 4. At the time, this sighting was even more widely reported than Arnold’s and lent considerable credence to Arnold’s report.

American UFO researcher Ted Bloecher, in his comprehensive review of newspaper reports (including cases that preceded Arnold's), found a sudden surge upwards in sightings on July 4, peaking on July 6–8. Bloecher noted that for the next few days most American newspapers were filled with front-page stories of the new "flying saucers" or "flying discs". Reports began to rapidly tail off after July 8 , when officials began issuing press statements on the Roswell UFO incident
Roswell UFO incident

The Roswell UFO Incident involved the recovery of materials near Roswell, New Mexico, USA, on July 7, 1947, and since the early 1980s has become the subject of intense speculation, rumor and questioning....
, in which they explained the debris as being that of a weather balloon.

Over several years in the 1960s, Bloecher (aided by physicist James E. McDonald
James E. McDonald

James E. McDonald was an United States physicist. He is best known for his research regarding unidentified flying object. McDonald was senior physicist at the Institute for Atmospheric Physics and professor in the Department of Meteorology, University of Arizona, Tucson....
) discovered 853 flying disc sightings that year from 140 newspapers from Canada, Washington D.C, and every U.S. state except Montana.

Investigation and responses

UFOs have been subject to various investigations over the years, varying widely in scope and scientific rigor. Governments or independent academics in the United States, Canada, the United Kingdom, France, Belgium, Sweden, Brazil, Chile, Mexico, Spain, and the Soviet Union are known to have investigated UFO reports at various times. Among the best known government studies are Project Blue Book
Project Blue Book

Project Blue Book was one of a series of systematic studies of Unidentified flying objects conducted by the United States Air Force . Started in 1952, it was the second revival of such a study....
, previously Project Sign
Project Sign

Project Sign was an official U.S. government study of unidentified flying objects undertaken by the United States Air Force in late 1947 and dissolved in late 1948....
 and Project Grudge
Project Grudge

Project Grudge was a short-lived project by the United States Air Force to investigate unidentified flying objects . Grudge succeeded Project Sign in February, 1949, and was then followed by Project Blue Book....
, conducted by the United States Air Force
United States Air Force

The United States Air Force is the aerial warfare branch of the Military of the United States and one of the uniformed services of the United States....
 from 1947 until 1969, the secret U.S. Army/Air Force Project Twinkle investigation into green fireballs
Green Fireballs

Green Fireballs is a self-descriptive term used to refer to certain unidentified flying objects which have been sighted in the sky since the late 1940s....
 (1948–1951), and Brazilian Air Force Operation Saucer (1977). A public research effort conducted by the Condon Committee
Condon Committee

The Condon Committee was the informal name of the University of Colorado UFO Project, a study of unidentified flying objects, undertaken at the University of Colorado at Boulder from 1966 to 1968 under the direction of physicist Edward Condon....
 for the USAF, which arrived at a negative conclusion in 1968, marked the end of the US government's official investigation of UFOs, though documents indicate various government intelligence agencies continue to unofficially investigate or monitor the situation.

No public government investigation has ever openly declared UFOs to be real, unexplained objects or of concern to national defense. (However, see below for some internal, secret studies that have concluded otherwise.) Some private studies have been neutral in their conclusions, but argued the inexplicable core cases called for continued scientific study. Examples are the Sturrock Panel study of 1998 and the 1970 AIAA review of the Condon Report.

American investigations

Following the large U.S. surge in sightings in June and early July 1947, on July 9, 1947, Army Air Force
United States Army Air Forces

The United States Army Air Forces was the military aviation arm of the United States of America during and immediately after World War II. The direct precursor to the United States Air Force, its peak size was over 2.4 million men and women in service and nearly 80,000 aircraft in 1944, and 783 domestic bases in December 1943....
 (AAF) intelligence, in cooperation with the FBI, began a formal investigation into selected best sightings with characteristics that could not be immediately rationalized, which included Kenneth Arnold
Kenneth Arnold

Kenneth A. Arnold was an American businessman and pilot.He is best-known for making what is generally considered the first widely reported unidentified flying object sighting in the United States, after claiming to see nine unusual objects flying in a chain near Mount Rainier, Washington on June 24, 1947....
’s and the United Airlines crew’s. The AAF used "all of its scientists" to determine whether or not "such a phenomenon could, in fact, occur". The research was "being conducted with the thought that the flying objects might be a celestial phenomenon," or that "they might be a foreign body mechanically devised and controlled." Three weeks later in a preliminary defense estimate, the air force investigation decided that, "This ‘flying saucer’ situation is not all imaginary or seeing too much in some natural phenomenon. Something is really flying around."

A further review by the intelligence and technical divisions of the Air Materiel Command at Wright Field reached the same conclusion, that "the phenomenon is something real and not visionary or fictitious," that there were objects in the shape of a disc, metallic in appearance, and as big as man-made aircraft. They were characterized by "extreme rates of climb [and] maneuverability," general lack of noise, absence of trail, occasional formation flying, and "evasive" behavior "when sighted or contacted by friendly aircraft and radar," suggesting a controlled craft. It was thus recommended in late September 1947 that an official Air Force investigation be set up to investigate the phenomenon. It was also recommended that other government agencies should assist in the investigation.

This led to the creation of the Air Force’s Project Sign
Project Sign

Project Sign was an official U.S. government study of unidentified flying objects undertaken by the United States Air Force in late 1947 and dissolved in late 1948....
 at the end of 1947, one of the earliest government studies to come to a secret extraterrestrial conclusion. In August 1948, Sign investigators wrote a top-secret intelligence estimate
Estimate of the Situation

The Estimate of the Situation was a document supposedly written in 1948 by the personnel of United States Air Force's Project Sign -including the project?s director, Captain Robert R....
 to that effect. The Air Force Chief of Staff Hoyt Vandenberg
Hoyt Vandenberg

Hoyt Sanford Vandenberg was a United States Air Force List of United States Air Force four-star generals, its second Chief of Staff of the United States Air Force, and the Director of the Central Intelligence Agency....
 ordered it destroyed. The existence of this suppressed report was revealed by several insiders who had read it, such as astronomer and USAF consultant Dr. J. Allen Hynek
J. Allen Hynek

Dr. Josef Allen Hynek was a United States astronomer, professor, and ufology.He is perhaps best remembered for his UFO research: Hynek acted as scientific adviser to UFO studies undertaken by the U.S....
 and Capt. Edward J. Ruppelt
Edward J. Ruppelt

Edward J. 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....
, the first head of the USAF's Project Blue Book
Project Blue Book

Project Blue Book was one of a series of systematic studies of Unidentified flying objects conducted by the United States Air Force . Started in 1952, it was the second revival of such a study....
.

Project Sign was dismantled and became Project Grudge
Project Grudge

Project Grudge was a short-lived project by the United States Air Force to investigate unidentified flying objects . Grudge succeeded Project Sign in February, 1949, and was then followed by Project Blue Book....
 at the end of 1948. Angered by the low quality of investigations by Grudge, the Air Force Director of Intelligence reorganized it as Project Blue Book
Project Blue Book

Project Blue Book was one of a series of systematic studies of Unidentified flying objects conducted by the United States Air Force . Started in 1952, it was the second revival of such a study....
 in late 1951, placing Ruppelt in charge. Blue Book closed down in 1970, ending the official Air Force UFO investigations. However, a 1969 USAF document, known as the Bolender memo, plus later government documents revealed that nonpublic U.S. government UFO investigations continued after 1970. The Bollender memo first stated that "reports of unidentified flying objects which could affect national security... are not part of the Blue Book system," indicating that more serious UFO incidents were already handled outside of the public Blue Book investigation. The memo then added, "reports of UFOs which could affect national security would continue to be handled through the standard Air Force procedures designed for this purpose."

Use of UFO instead of the popular flying saucer
Flying saucer

Flying saucer is the name given to a type of unidentified flying object with a disc- or saucer-shaped body, usually described as silver or metallic, occasionally reported as covered with running lights or surrounded with a glowing light, hovering or moving rapidly either alone or in tight formations with other similar craft, and exhibiting...
 was first suggested in 1952 by Ruppelt, who felt that flying saucer did not reflect the diversity of the sightings. Ruppelt suggested that UFO should be pronounced as a word — you-foe. However it is generally pronounced by forming each letter: U.F.O. His term was quickly adopted by the Air Force, which also briefly used "UFOB" circa 1954, for Unidentified Flying Object. Ruppelt recounted his experiences with Project Blue Book in his memoir, The Report on Unidentified Flying Objects (1956), also the first book to use the term.

, issued in 1953 and 1954, defined an Unidentified Flying Object ("UFOB") as "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 identified as a familiar object." The regulation also said UFOBs were to be investigated as a "possible threat to the security of the United States" and "to determine technical aspects involved." As with any then-ongoing investigation, Air Force personnel did not discuss the investigation with the press.

Well known American investigations include:

  • Project Blue Book
    Project Blue Book

    Project Blue Book was one of a series of systematic studies of Unidentified flying objects conducted by the United States Air Force . Started in 1952, it was the second revival of such a study....
    , previously Project Sign
    Project Sign

    Project Sign was an official U.S. government study of unidentified flying objects undertaken by the United States Air Force in late 1947 and dissolved in late 1948....
     and Project Grudge
    Project Grudge

    Project Grudge was a short-lived project by the United States Air Force to investigate unidentified flying objects . Grudge succeeded Project Sign in February, 1949, and was then followed by Project Blue Book....
    , conducted by the United States Air Force
    United States Air Force

    The United States Air Force is the aerial warfare branch of the Military of the United States and one of the uniformed services of the United States....
     from 1947 until 1969
  • The secret U.S. Army/Air Force Project Twinkle investigation into green fireballs
    Green Fireballs

    Green Fireballs is a self-descriptive term used to refer to certain unidentified flying objects which have been sighted in the sky since the late 1940s....
     (1948–1951)
  • Ghost rockets
    Ghost rockets

    Ghost Rockets were mysterious rocket- or missile-shaped unidentified flying objects sighted in 1946, mostly in Sweden and nearby countries.About 2000 ghost rockets sightings were logged between May and December 1946, with peaks on the 9 and 11 August 1946....
     investigations by the Swedish, U.K., U.S., and Greek militaries (1946–1947)
  • The secret CIA Robertson Panel
    Robertson Panel

    The Robertson Panel was a committee commissioned by the Central Intelligence Agency in 1952 in response to widespread reports of unidentified flying objects, especially in the Washington, D.C....
     (1953)
  • The secret USAF Project Blue Book Special Report No. 14
    Identified Flying Object

    see Identified flying object for IFOs in ufology Identified Flying Object is an album by the goa trance project Pleiadians. It was released in 1997 by Dragonfly Records....
     by the Battelle Memorial Institute
    Battelle Memorial Institute

    The Battelle Memorial Institute is a private nonprofit corporation applied science and technology development company headquartered in Columbus, Ohio....
     (1951–1954)
  • The Brookings Report
    Brookings Report

    The Brookings Report or Proposed Studies on the Implications of Peaceful Space Activities for Human Affairs, was commissioned by NASA and created by the Brookings Institution; it was submitted to the United States House of Representatives in the 87th United States Congress on April 18, 1961....
     (1960), commissioned by NASA
    NASA

    The National Aeronautics and Space Administration is an agency of the Federal government of the United States, responsible for the nation's public list of space agencies....
  • The public Condon Committee (1966–1968)
  • The private Sturrock Panel
    Peter A. Sturrock

    Peter Andrew Sturrock is a United Kingdom scientist.An emeritus professor of applied physics at Stanford University, much of Sturrock's career has been devoted to astrophysics, plasma physics, and solar physics, but Sturrock is interested in other fields, including ufology, scientific inference and in the history of science and philosophy...
     (1998)


Another early U.S. Army study, established sometime in the 1940s and of which little is known, was called the Interplanetary Phenomenon Unit (IPU). In 1987, British UFO researcher Timothy Good
Timothy Good

Timothy Good is a British Ufology and professional violinist.He was born in London and educated at The King's School, Canterbury, Canterbury before being granted a scholarship to the Royal Academy of Music, where he studied the violin....
 received a letter confirming the existence of the IPU from the Army Director of Counter-intelligence, in which it was stated, "...the aforementioned Army unit was disestablished during the late 1950s and never reactivated. All records pertaining to this unit were surrendered to the U.S. Air Force Office of Special Investigations
Air Force Office of Special Investigations

The Air Force Office of Special Investigations , is a List of United States Air Force Field Operating Agencies of the United States Air Force that provides professional investigative services to commanders throughout the Air Force....
 in conjunction with operation BLUEBOOK." The IPU records have never been released.

Thousands of documents released under FOIA
Freedom of Information Act (United States)

The Freedom of Information Act is the implementation of freedom of information freedom of information in the United States in the United States....
 also indicate that many U.S. intelligence agencies collected (and still collect) information on UFOs, including the Defense Intelligence Agency
Defense Intelligence Agency

The Defense Intelligence Agency, or DIA, is a major producer and manager of military intelligence for the United States Department of Defense, employing over 11,000 military and civilian employees worldwide....
 (DIA), FBI, CIA, National Security Agency
National Security Agency

The National Security Agency/Central Security Service is a Cryptology Intelligence agency of the Federal government of the United States, administered as part of the United States Department of Defense....
 (NSA), as well as military intelligence agencies of the Army and Navy, in addition to the Air Force.

The investigation of UFOs has also attracted many civilians, who in the U.S formed research groups such as National Investigations Committee On Aerial Phenomena
National Investigations Committee On Aerial Phenomena

The National Investigations Committee On Aerial Phenomena was a civilian unidentified flying object research group active in the United States from the 1950s to the 1980s....
 (NICAP, active 1956-1980), Aerial Phenomena Research Organization
Aerial Phenomena Research Organization

The Aerial Phenomena Research Organization was a unidentified flying object research group started in 1952 by Jim Lorenzen and Coral Lorenzen Lorenzen....
 (APRO, 1952-1988), Mutual UFO Network
Mutual UFO Network

The Mutual UFO Network, or MUFON, is one of the oldest and largest Unidentified flying object investigative organizations in the United States....
 (MUFON, 1969-), and Center for UFO Studies
Center for UFO Studies

The Center for UFO Studies is a privately-funded unidentified flying object research group. It was founded in 1973 by J. Allen Hynek, the Chairman of the Department of Astronomy at Northwestern University in Illinois....
 (CUFOS, 1973-).

Canadian investigation

In Canada, the Department of National Defence has dealt with reports, sightings and investigations of UFOs across Canada. In addition to conducting investigations into crop circles
Crop Circles

Crop Circles was a collaboration between the psychedelic trance band Etnica and a Milanese group called Lotus Omega . An album, entitled "Tetrahedron", should have been released around 1998, but the project was abandoned because the British label Auracle Recordings went bankrupt....
 in Duhamel, Alberta
Duhamel, Alberta

Duhamel is a small rural Hamlet located in the central prairies of Alberta, Canada. It is located on Alberta Highway 21, at , approximately 100 km SSE of Edmonton, Alberta and 20 km SW of Camrose, Alberta, the closest major trading center....
, it still identifies the Falcon Lake incident
Falcon Lake Incident

The Falcon Lake Incident occurred on May 20, 1967, when Stefan Michalak claimed that he encountered a unidentified flying object near Falcon Lake, Manitoba, Canada....
 in Manitoba
Manitoba

Manitoba is a prairie provinces in Canada, which has an area of 647,797 square kilometres and a population of 1,207,959 , with more than half located within the Winnipeg Capital Region ....
 and the Shag Harbour incident in Nova Scotia
Nova Scotia

Nova Scotia is a Canadian Provinces and territories of Canada located on Canada's southeastern coast. It is the most populous province in Atlantic Canada....
 as "unsolved".

The Canadian studies include Project Magnet
Project Magnet

Project Magnet was an unidentified flying object study programme established by the Canada Transport Canada on December 2, 1950, under the direction of Wilbert B....
 (1950–1954) and Project Second Story (1952–1954)

French investigation

In March 2007, the French Centre National d'Études Spatiales (CNES) published an archive of UFO sightings and other phenomena online.

French studies include GEPAN/SEPRA/GEIPAN
GEIPAN

GEIPAN , formerly known as GEPAN and SEPRA , is a unit of the French Space Agency CNES whose brief is to investigate unidentified aerospace phenomena and make its findings available to the public....
 (1977–), within the French space agency CNES
CNES

The is the France government space agency . Its headquarters are located in central Paris. It operates out of the Centre Spatial Guyanais, but also has payloads launched from other space centres operated by other countries....
, the longest ongoing government-sponsored investigation, and the private French COMETA
COMETA

COMETA was a high-level France UFO study organisation from the late 1990s, composed of high-ranking officers and officials, some having held command posts in the armed forces and aerospace industry....
 panel (1996–1999)

British investigation

The UK conducted various investigations into UFO sightings and related stories. The contents of some of these investigations have since been released to the public.

Eight file collections on UFO sightings, dating from 1978 to 1987, were first released on May 14, 2008, to the UK National Archives by the Ministry of Defence
Ministry of Defence (United Kingdom)

The Ministry of Defence is the Departments of the United Kingdom Government responsible for implementation of government defence policy and is the headquarters of the British Armed Forces....
. Although kept secret from the public for many years, most of the files have low levels of classification and none is classified Top Secret. 200 files are set to be made public by 2012. The files are correspondence from the public sent to government officials, such as the MoD and Margaret Thatcher
Margaret Thatcher

Margaret Hilda Thatcher, Baroness Thatcher Order of the Garter, Order of Merit, Her Majesty's Most Honourable Privy Council, Fellow of the Royal Society was Prime Minister of the United Kingdom from 1979 to 1990 and Leader of the Conservative Party of the Conservative Party from 1975 to 1990....
. The MoD released the files under the Freedom of Information Act
Freedom of information in the United Kingdom

Freedom of information legislation in the United Kingdom is controlled by two Acts of Parliament respectively, which both came into force on 1 January 2005....
 due to requests from researchers. These files include, but are not limited to, UFOs over Liverpool
Liverpool

Liverpool [] is a city and metropolitan borough of Merseyside, England, along the eastern side of the Mersey Estuary. It was founded as a History of borough status in England and Wales in 1207 and was granted City status in the United Kingdom in 1880....
 and the Waterloo Bridge
Waterloo Bridge

Waterloo Bridge is a road and foot traffic bridge crossing the River Thames in London, England between Blackfriars Bridge and Hungerford Bridge....
 in London.

On October 20, 2008 more UFO files were released. One case released detailed that in 1991 an Alitalia
Alitalia

AlitaliaCompagnia Aerea Italiana S.p.A. , is an Italian airline. It has bought some assets of Alitalia - Linee Aeree Italiane S.p.A. . Headquartered in Rome, it operates services to 24 domestic and 66 international destinations....
 passenger aircraft was approaching Heathrow Airport when the pilots saw what they described as a "cruise missile
Cruise missile

A cruise missile is a guided missile missile that carries an explosive payload and uses a lifting wing and a propulsion system, usually a jet engine, to allow sustained flight; it is essentially a flying bomb....
" flew extremely close to the cockpit. The pilots believed that a collision was imminent. UFO expert Dr David Clarke says that this is one of the most convincing cases for a UFO he has come across.

British investigations include The UK's Flying Saucer Working Party
Flying Saucer Working Party

The Ministry of Defence ?s first "official study into UFOs" was called Flying Saucer Working Party or the FSWP which has its roots in a study commissioned in 1950 by the MOD?s then Chief Scientific Adviser, the great radar scientist Sir Henry Tizard....
. Its final report, published in 1951, remained secret for over 50 years. The Working Party concluded that all UFO sightings could be explained as misidentifications of ordinary objects or phenomena, optical illusions, psychological delusions or hoaxes. The report stated: ‘We accordingly recommend very strongly that no further investigation of reported mysterious aerial phenomena be undertaken, unless and until some material evidence becomes available’.

A secret study of UFOs undertaken for the UK’s Ministry of Defence (MoD) between 1996 and 2000 and was publicly released in 2006. The report is titled "Unidentified Aerial Phenomena in the UK Defence Region" and was code-named Project Condign
Project Condign

Project Condign was the name given to a top-secret UFO study undertaken by the British Government's Defence Intelligence Staff between 1997 and 2000....
. The report confirmed earlier findings that the main causes of UFO sightings are misidentification of man-made and natural objects. The report noted: "No artefacts of unknown or unexplained origin have been reported or handed to the UK authorities, despite thousands of UAP reports. There are no SIGINT
SIGINT

Signals intelligence is list of intelligence gathering disciplines by interception of signals, whether between people or between machines , or mixtures of the two....
, ELINT or radiation measurements and little useful video or still IMINT
IMINT

IMINT, short for IMagery INTelligence, is an list of intelligence gathering disciplines which collects information via satellite and aerial photography....
." It concluded: "There is no evidence that any UAP, seen in the UKADR [UK Air Defence Region], are incursions by air-objects of any intelligent (extraterrestrial or foreign) origin, or that they represent any hostile intent."

In contrast, Nick Pope
Nick Pope

Nick Pope is a 25 year serving former employee of the British Government's Ministry of Defence . He is most notable for having served as a regular term between 1991 and 1994 as that agency's official first point of contact and investigator of UFO reports and sightings, in the department then known as Sec2a ....
, who headed the MoD UFO desk from 1991-1994, states that while about 80% of the cases he investigated were misidentifications of known objects and phenomena (while 15% of sightings had insufficient information), about 5% "seemed to defy any conventional explanation." These included cases with multiple and/or highly trained witnesses such as pilots or military personnel, corroboration from radar or video/photography, and involved apparent structured craft with speeds and maneuverability beyond that of human origin. Stopping short of an extraterrestrial explanation (though not discounting it), Pope believes the UFO phenomenon is quite real and raises serious defense, national security, and air safety issues. Pope describes many of the perplexing cases, such as the Rendlesham Forest incident
Rendlesham Forest Incident

The Rendlesham Forest Incident is the name given to a series of reported sightings of unexplained lights and the alleged landing of an extraterrestrial life spacecraft in Rendlesham Forest, Suffolk, England in late December 1980....
, and the politics surrounding UFOs in his book Open Skies, Closed Minds.

Astronomer reports

The Air Force's Project Blue Book
Project Blue Book

Project Blue Book was one of a series of systematic studies of Unidentified flying objects conducted by the United States Air Force . Started in 1952, it was the second revival of such a study....
 files indicate that approximately 1% of all unknown reports came from amateur and professional astronomers or other users of telescopes (such as missile trackers or surveyors). In the 1970s, astrophysicist Peter A. Sturrock
Peter A. Sturrock

Peter Andrew Sturrock is a United Kingdom scientist.An emeritus professor of applied physics at Stanford University, much of Sturrock's career has been devoted to astrophysics, plasma physics, and solar physics, but Sturrock is interested in other fields, including ufology, scientific inference and in the history of science and philosophy...
 conducted two surveys of the American Institute of Aeronautics and Astronautics
American Institute of Aeronautics and Astronautics

The American Institute of Aeronautics and Astronautics is the professional society for the field of aerospace engineering. The AIAA was founded in 1963 from the merger of two earlier societies: the American Rocket Society , founded in 1930 as the American Interplanetary Society , and the Institute of Aerospace Sciences , founded...
 and American Astronomical Society
American Astronomical Society

The American Astronomical Society is a United States society of professional astronomy and other interested individuals, headquartered in Washington, DC....
. About 5% of the members polled indicated that they had had UFO sightings. In 1980, a survey of 1800 members of various amateur astronomer associations by Gert Helb and astronomer J. Allen Hynek
J. Allen Hynek

Dr. Josef Allen Hynek was a United States astronomer, professor, and ufology.He is perhaps best remembered for his UFO research: Hynek acted as scientific adviser to UFO studies undertaken by the U.S....
 of the Center for UFO Studies
Center for UFO Studies

The Center for UFO Studies is a privately-funded unidentified flying object research group. It was founded in 1973 by J. Allen Hynek, the Chairman of the Department of Astronomy at Northwestern University in Illinois....
 (CUFOS) found that 24% responded "yes" to the question "Have you ever observed an object which resisted your most exhaustive efforts at identification?"

Astronomer Clyde Tombaugh
Clyde Tombaugh

Clyde William Tombaugh was an United States astronomer.Tombaugh is best known for discovering the dwarf planet Pluto in 1930, but also discovered many asteroids, and called for serious scientific research of unidentified flying objects....
, who admitted to six UFO sightings, including three green fireballs
Green Fireballs

Green Fireballs is a self-descriptive term used to refer to certain unidentified flying objects which have been sighted in the sky since the late 1940s....
 supported the Extraterrestrial hypothesis (ETH) for UFOs and stated he thought scientists who dismissed it without study were being "unscientific." Another astronomer was Dr. Lincoln LaPaz
Lincoln LaPaz

Lincoln LaPaz was an American astronomer from the University of New Mexico and a pioneer in the study of meteors.He was born in Wichita, Kansas on February 12, 1897 to Charles Melchior LaPaz and Emma Josephine ....
, who had headed the Air Force's investigation into the green fireballs and other UFO phenomena in New Mexico. LaPaz reported two personal sightings, one of a green fireball, the other of an anomalous disc-like object. Even later UFO debunker Dr. Donald Menzel filed a UFO report in 1949.

Identification of UFOs


Studies show that after careful investigation, the majority of UFOs can be identified as ordinary objects or phenomena (see Identification studies of UFOs). The most commonly found identified sources of UFO reports are:
  • Astronomical objects (bright stars, planets, meteors, re-entering man-made spacecraft, artificial satellites, and the moon)
  • Aircraft (advertising planes and other aircraft, missile launches)
  • Balloons (weather balloons, prank balloons, large research balloons)


Much less common sources of UFO reports include:
  • Other atmospheric objects and phenomena (birds, unusual clouds, kites, flares)
  • Light phenomena (mirage
    Mirage

    A mirage is a naturally occurring optical phenomenon in which light rays are bent to produce a displaced image of distant objects or the sky. The word comes to English via the French language mirage, from the Latin mirare, meaning "to look at, to wonder at"....
    s, Fata Morgana
    Mirage

    A mirage is a naturally occurring optical phenomenon in which light rays are bent to produce a displaced image of distant objects or the sky. The word comes to English via the French language mirage, from the Latin mirare, meaning "to look at, to wonder at"....
    , moon dog
    Moon dog

    A moon dog or moondog is a relatively rare bright circular spot on a lunar Halo caused by the refraction of moonlight by hexagonal-plate-shaped ice in Cirrus cloud or cirrostratus clouds....
    s, searchlight
    Searchlight

    A searchlight is an apparatus with reflectors for projecting a powerful beam of light of approximately parallel rays in a particular direction,...
    s and other ground lights, etc.)
  • Hoaxes


A study
Project Blue Book

Project Blue Book was one of a series of systematic studies of Unidentified flying objects conducted by the United States Air Force . Started in 1952, it was the second revival of such a study....
 by the Battelle Memorial Institute
Battelle Memorial Institute

The Battelle Memorial Institute is a private nonprofit corporation applied science and technology development company headquartered in Columbus, Ohio....
 of US Air Force reports included these categories as well as a "psychological" one. However, the scientific analysts were unable to come up with prosaic explanations for 21.5% of the 3200 cases they examined and 33% of what were considered the best cases remained unexplained, double the number of the worst cases. (See full statistical breakdown in Identification studies of UFOs). Of the 69% identifieds, 38% were deemed definitely explained while 31% were thought to be "questionable." About 9% of the cases were considered to have insufficient information to make a determination.

The official French government UFO investigation (GEPAN/SEPRA), run within the French space agency CNES between 1977 and 2004, scientifically investigated about 6000 cases and found that 13.5% defied any rational explanation, 46% were deemed definitely or likely identifiable, while 41% lacked sufficient information for classification.

An individual 1979 study by CUFOS researcher Allan Hendry
Allan Hendry

Allan Hendry is an American astronomer and ufology. UFO historian Jerome Clark calls him "one of the most skilled investigators in the history of UFO research." He was the main investigator for the Center for UFO Studies in the 1970s....
 found, as did other investigations, that only a small percentage of cases he investigated were hoaxes (<1%) and that most sightings were actually honest misidentifications of prosaic phenomena. Hendry attributed most of these to inexperience or misperception. However, Hendry's figure for unidentified cases was considerably lower than many other UFO studies such as Project Blue Book
Project Blue Book

Project Blue Book was one of a series of systematic studies of Unidentified flying objects conducted by the United States Air Force . Started in 1952, it was the second revival of such a study....
 or the Condon Report which have found rates of unidentified cases ranging from 6% to 30%. Hendry found that 88.6% of the cases he studied had a clear prosaic explanation, and he discarded a further 2.8% due to unreliable or contradictory witnesses or insufficient information. The remaining 8.6% of reports could not definitively be explained by prosaic phenomena, although he felt that a further 7.1% could possibly be explained, leaving only the very best 1.5% without plausible explanation.

UFO hypotheses


To account for unsolved UFO cases, several hypotheses have been proposed.

  • The Extraterrestrial hypothesis
    Extraterrestrial hypothesis

    The extraterrestrial hypothesis is the hypothesis that some unidentified flying objects are best explained as being extraterrestrial life or space aliens from extrasolar planets occupying physical spacecraft visiting Earth....
     (ETH), defined by Edward U. Condon in the 1968 Condon 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
    Donald Keyhoe

    Donald Edward Keyhoe was an United States United States Marine Corps officer with some flight experience, writer of many aviation articles and stories in a variety of leading publications, and manager of the promotional tours of aviation pioneers, especially of Charles Lindbergh....
    's UFO book from 1950 , though the idea clearly predated Keyhoe, appearing in newspapers and various government documents (see immediately below). This is probably the most popular theory among Ufologists.
  • The Interdimensional hypothesis
    Interdimensional hypothesis

    Interdimensional hypothesis is a theory advanced by Jacques Vallee that unidentified flying objects and related events involve visitations from other "realities" or "dimensions" coexisting separately alongside our own....
    , that UFOs are objects crossing over from other dimensions or parallel universe
    Parallel universe

    Parallel universe may refer to:* Multiverse, the hypothetical set of multiple possible universes* Many-worlds interpretation, of quantum physics...
    , popularly proposed by Jacques Vallée
    Jacques Vallée

    Jacques F. Vall?e, Ph.D. , is a French-born venture capitalist, computer scientist, ufology and former astronomer, currently residing in San Francisco, California in the United States....
    , though also predating him.
  • The Paranormal/Occult Hypothesis
    Paranormal and occult hypotheses about UFOs

    There has been a fair amount of crossover between paranormal events and unidentified flying objects. Both are sometimes seen as dubious fields of study by mainstream science, and generally, have seen little support....
    ; A variant of the Interdimensional Hypothesis, invoked to explain so-called paranormal
    Paranormal

    Paranormal is a general term that describes unusual experiences that lack a scientific explanation, or phenomena alleged to be outside of science's current ability to explain or measure....
     aspects sometimes associated with UFO reports
  • That UFOs are time machine
    Time travel

    Time travel is the concept of moving between different moments in time in a manner analogous to moving between different points in space, either sending objects backwards in time to a moment before the present, or sending objects forward from the present to the future without the need to experience the intervening period ....
    s or vehicles from a future Earth, perhaps made by our descendants.
  • The Psychosocial Hypothesis
    Psychosocial Hypothesis

    In ufology, the psychosocial or psychocultural hypothesis, colloquially abbreviated PSH or PCH, argues that at least some Unidentified flying object reports are best explained by psychology or anthropological means....
    , that what people report as UFO experiences is the result of psychological misperception mechanisms and is strongly influenced by popular culture.
  • That UFOs represent poorly understood or still unknown natural phenomena, such as ball lightning
    Ball lightning

    Ball lightning may be an atmospheric electricity phenomenon, the physical nature of which is still controversial. The term refers to reports of luminous, usually spherical objects which vary from pea-sized to several meters in diameter....
     or sprites
    Lightning

    File:Blesk.jpgLightning is an Earth's atmosphere discharge of electricity usually accompanied by thunder, which typically occurs during thunderstorms, and sometimes during volcano or dust storms....
    .
  • The Earthquake lights/Tectonic Strain hypothesis
    Michael Persinger

    Dr. Michael A. Persinger , is a cognitive neuroscience researcher and university professor He has worked at Laurentian University, Canada since 1971 ....
    : UFOs are caused by strains in Earth's crust near earthquake faults, which can also supposedly induce hallucinations.
  • That UFOs are military flying saucers
    Military flying saucers

    The development of disc shaped aircraft ? or military "flying saucers" ? apparently dates back to World War II. Since most of the information is highly classified, many details are uncertain....
    ; top secret or experimental aircraft unfamiliar to most people.


Documents and investigations regarding the Extraterrestrial Hypothesis

Other private or governmental studies, some secret, have concluded in favor of the Extraterrestrial hypothesis (ETH), or have had members who disagreed with official conclusions against the conclusion by committees and agencies to which they belonged. The following are examples of sources that have focused specifically on the topic:

  • In 1967, Greek physicist Paul Santorini, a Manhattan Project
    Manhattan Project

    The Manhattan Project was the project to develop the first atomic weapon during World War II; involving the United States, the United Kingdom, and Canada....
     scientist, publicly stated that a 1947 Greek government investigation that he headed into the European Ghost rockets
    Ghost rockets

    Ghost Rockets were mysterious rocket- or missile-shaped unidentified flying objects sighted in 1946, mostly in Sweden and nearby countries.About 2000 ghost rockets sightings were logged between May and December 1946, with peaks on the 9 and 11 August 1946....
     of 1946 quickly concluded that they were not missiles. Santorini claimed the investigation was then quashed by military officials from the U.S., who knew them to be extraterrestrial, because there was no defense against the advanced technology and they feared widespread panic should the results become public.
  • A 1948 Top Secret USAF Europe document (at right) states that Swedish air intelligence informed them that at least some of their investigators into the ghost rockets and flying saucers concluded they had extraterrestrial origins: "...Flying saucers have been reported by so many sources and from such a variety of places that we are convinced that they cannot be disregarded and must be explained on some basis which is perhaps slightly beyond the scope of our present intelligence thinking. When officers of this Directorate recently visited the Swedish Air Intelligence Service... their answer was that some reliable and fully technically qualified people have reached the conclusion that 'these phenomena are obviously the result of a high technical skill which cannot be credited to any presently known culture on earth.' They are therefore assuming that these objects originate from some previously unknown or unidentified technology, possibly outside the earth."
  • In 1948, the USAF's Project Sign
    Project Sign

    Project Sign was an official U.S. government study of unidentified flying objects undertaken by the United States Air Force in late 1947 and dissolved in late 1948....
     wrote a Top Secret Estimate of the Situation
    Estimate of the Situation

    The Estimate of the Situation was a document supposedly written in 1948 by the personnel of United States Air Force's Project Sign -including the project?s director, Captain Robert R....
    , concluding that the ETH was the most likely explanation for the most perplexing unexplained cases. The study was ordered destroyed by USAF chief of staff General Hoyt Vandenberg
    Hoyt Vandenberg

    Hoyt Sanford Vandenberg was a United States Air Force List of United States Air Force four-star generals, its second Chief of Staff of the United States Air Force, and the Director of the Central Intelligence Agency....
    , citing lack of proof. Knowledge of the existence of the Estimate has come from insiders who said they read a surviving copy, including later USAF Project Blue Book
    Project Blue Book

    Project Blue Book was one of a series of systematic studies of Unidentified flying objects conducted by the United States Air Force . Started in 1952, it was the second revival of such a study....
     head Edward J. Ruppelt
    Edward J. Ruppelt

    Edward J. 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....
     and astronomer and USAF consultant Dr. J. Allen Hynek
    J. Allen Hynek

    Dr. Josef Allen Hynek was a United States astronomer, professor, and ufology.He is perhaps best remembered for his UFO research: Hynek acted as scientific adviser to UFO studies undertaken by the U.S....
    .
  • West Germany, in conjunction with other European countries, conducted a secret study from 1951 to 1954, also concluding that UFOs were extraterrestrial. This study was revealed by German rocketry pioneer Hermann Oberth
    Hermann Oberth

    Hermann Julius Oberth was a Transylvania born, physicist, and, along with the Russian Konstantin Tsiolkovsky and the United States Robert Goddard , one of the founding fathers of rocketry and astronautics....
    , who headed the study and who also made many public statements supporting the ETH in succeeding years. At the study's conclusion in 1954, Oberth declared, "These objects (UFOs) are conceived and directed by intelligent beings of a very high order. They do not originate in our solar system, perhaps not in our galaxy." Soon afterwards, in an article in The American Weekly, October 24, 1954, Oberth wrote "It is my thesis that flying saucers are real and that they are space ships from another solar system. I think that they possibly are manned by intelligent observers who are members of a race that may have been investigating our earth for centuries..."
  • During the height of the flying saucer "flap" of July 1952, including highly publicized radar/visual and jet intercepts over Washington, D.C.
    Washington, D.C.

    Washington, D.C. , formally the District of Columbia and commonly referred to as Washington, the District, or simply D.C., is the Capital of the United States, founded on July 16, 1790....
    , the FBI was informed by the Air Force Directorate of Intelligence that they thought the "flying saucers" were either "optical illusions or atmospheric phenomena" but then added that, "some Military officials are seriously considering the possibility of interplanetary ships."
  • The CIA started their own internal scientific review the following day. Some CIA scientists were also seriously considering the ETH. An early memo from August was very skeptical, but also added, "...as long as a series of reports remains 'unexplainable' (interplanetary aspects and alien origin not being thoroughly excluded from consideration) caution requires that intelligence continue coverage of the subject." A report from later that month was similarly skeptical but nevertheless concluded "...sightings of UFOs reported at Los Alamos
    Los Alamos National Laboratory

    Los Alamos National Laboratory is a United States Department of Energy United States Department of Energy National Labs, managed and operated by Los Alamos National Security, LLC , located in Los Alamos, New Mexico....
     and Oak Ridge
    Oak Ridge National Laboratory

    Oak Ridge National Laboratory is a multiprogram science and technology national laboratory managed for the United States Department of Energy by UT-Battelle....
    , at a time when the background radiation
    Radiation

    In physics, radiation describes any process in which energy emitted by one body travels through a medium or through space, ultimately to be absorbed by another body....
     count had risen inexplicably. Here we run out of even 'blue yonder' explanations that might be tenable, and we still are left with numbers of incredible reports from credible observers." A December 1952 memo from the Assistant CIA Director of Scientific Intelligence (O/SI) was much more urgent: "...the reports of incidents convince us that there is something going on that must have immediate attention. Sightings of unexplained objects at great altitudes and traveling at highs speeds in the vicinity of U.S. defense installation are of such nature that they are not attributable to natural phenomena or known types of aerial vehicles." Some of the memos also made it clear that CIA interest in the subject was not to be made public, partly in fear of possible public panic. (Good, 331–335)
  • The CIA organized the January 1953 Robertson Panel
    Robertson Panel

    The Robertson Panel was a committee commissioned by the Central Intelligence Agency in 1952 in response to widespread reports of unidentified flying objects, especially in the Washington, D.C....
     of scientists to debunk the data collected by the Air Force's Project Blue Book
    Project Blue Book

    Project Blue Book was one of a series of systematic studies of Unidentified flying objects conducted by the United States Air Force . Started in 1952, it was the second revival of such a study....
    . This included an engineering analysis of UFO maneuvers by Blue Book (including a motion picture film analysis by Naval scientists) that had concluded UFOs were under intelligent control and likely extraterrestrial.
  • Extraterrestrial "believers" within Project Blue Book
    Project Blue Book

    Project Blue Book was one of a series of systematic studies of Unidentified flying objects conducted by the United States Air Force . Started in 1952, it was the second revival of such a study....
     included Major Dewey Fournet, in charge of the engineering analysis of UFO motion, who later became a board member on the civilian UFO organization NICAP. Blue Book director Edward J. Ruppelt
    Edward J. Ruppelt

    Edward J. 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....
     privately commented on other firm "pro-UFO" members in the USAF investigations, including some Pentagon generals, such as Charles P. Cabell
    Charles P. Cabell

    Charles Pearre Cabell was an United States Air Force General officer and deputy director of the Central Intelligence Agency....
    , USAF Chief of Air Intelligence, who angry at the inaction and debunkery of Project Grudge
    Project Grudge

    Project Grudge was a short-lived project by the United States Air Force to investigate unidentified flying objects . Grudge succeeded Project Sign in February, 1949, and was then followed by Project Blue Book....
    , dissolved it in 1951, established Project Blue Book in its place, and made Ruppelt director. In 1953, Cabell became deputy director of the CIA. Another defector from the official Air Force party line was consultant Dr. J. Allen Hynek
    J. Allen Hynek

    Dr. Josef Allen Hynek was a United States astronomer, professor, and ufology.He is perhaps best remembered for his UFO research: Hynek acted as scientific adviser to UFO studies undertaken by the U.S....
    , who started out as a staunch skeptic. After 20 years of investigation, he changed positions and generally supported the ETH. He became the most publicly known UFO advocate scientist in the 1970s and 1980s.
  • The first CIA Director, Vice Admiral Roscoe H. Hillenkoetter
    Roscoe H. Hillenkoetter

    Roscoe Henry Hillenkoetter , born in St. Louis, Missouri, was the third director of the post-WWII U.S. Central Intelligence Group and the first director of the Central Intelligence Agency created by the National Security Act of 1947....
    , stated in a signed statement to Congress, also reported in the New York Times, February 28, 1960, "It is time for the truth to be brought out... Behind the scenes high-ranking Air Force officers are soberly concerned about the UFOs. However, through official secrecy and ridicule, many citizens are led to believe the unknown flying objects are nonsense... I urge immediate Congressional action to reduce the dangers from secrecy about unidentified flying objects." In 1962, in his letter of resignation from NICAP, he told director Donald Keyhoe
    Donald Keyhoe

    Donald Edward Keyhoe was an United States United States Marine Corps officer with some flight experience, writer of many aviation articles and stories in a variety of leading publications, and manager of the promotional tours of aviation pioneers, especially of Charles Lindbergh....
    , "I know the UFOs are not U.S. or Soviet devices. All we can do now is wait for some actions by the UFOs."
  • Although the 1968 Condon Report came to a negative conclusion (written by Condon
    Edward Condon

    Edward Uhler Condon was a distinguished United States nuclear physicist, a pioneer in quantum mechanics, a participant in the development of radar and nuclear weapons in World War II, research director of Corning Glass, director of the National Bureau of Standards, and president of the American Physical Society ....
    ), it is known that many members of the study strongly disagreed with Condon's methods and biases. Most quit the project in disgust or were fired for insubordination. A few became ETH supporters. Perhaps the best known example is Dr. David Saunders, who in his 1968 book UFOs? Yes lambasted Condon for extreme bias and ignoring or misrepresenting critical evidence. Saunders wrote, "It is clear... that the sightings have been going on for too long to explain in terms of straightforward terrestrial intelligence. It's in this sense that ETI (Extra Terrestrial Intelligence) stands as the 'least implausible' explanation of 'real UFOs'."
  • In 1999, the private French COMETA
    COMETA

    COMETA was a high-level France UFO study organisation from the late 1990s, composed of high-ranking officers and officials, some having held command posts in the armed forces and aerospace industry....
     report (written primarily by military defense analysts) stated the conclusion regarding UFO phenomena, that a "single hypothesis sufficiently takes into account the facts and, for the most part, only calls for present-day science. It is the hypothesis of extraterrestrial visitors." The report noted issues with formulating the extraterrestrial hypothesis, likening its study to the study of meteorites, but concluded that although it was far from the best scientific hypothesis, "strong presumptions exist in its favour". The report also concludes that the studies it presents "demonstrate the almost certain physical reality of completely unknown flying objects with remarkable flight performances and noiselessness, apparently operated by intelligent [beings] … Secret craft definitely of early origins (drones, stealth aircraft, etc.) can only explain a minority of cases. If we go back far enough in time, we clearly perceive the limits of this explanation."
  • Jean-Jacques Velasco, the head of the official French UFO investigation SEPRA, wrote a book in 2005 saying that 14% of the 5800 cases studied by SEPRA were utterly inexplicable and extraterrestrial in origin. Yves Sillard, the head of the new official French UFO investigation GEIPAN
    GEIPAN

    GEIPAN , formerly known as GEPAN and SEPRA , is a unit of the French Space Agency CNES whose brief is to investigate unidentified aerospace phenomena and make its findings available to the public....
     and former head of the French space agency CNES
    CNES

    The is the France government space agency . Its headquarters are located in central Paris. It operates out of the Centre Spatial Guyanais, but also has payloads launched from other space centres operated by other countries....
    , echoes Velasco's comments and adds the U.S. is guilty of covering up this information. Again, this isn't the official public posture of SEPRA, CNES, or the French government. (CNES recently placed their 5800 case files on the Internet starting March 2007.)


Physical evidence

Besides visual sightings, reports sometimes include claims of indirect and direct physical evidence, including cases studied by the military and various government agencies of different countries.

  • Radar
    Radar

    Radar is a system that uses electromagnetic radiation waves to identify the range, altitude, direction, or speed of both moving and fixed objects such as aircraft, ships, motor vehicles, weather formations, and terrain....
     contact and tracking, sometimes from multiple sites. These may involve trained military personnel and control tower operators, simultaneous visual sightings, and aircraft intercepts. One such recent example were the mass sightings of large, silent, low-flying black triangles in 1989 and 1990 over Belgium, tracked by multiple NATO
    NATO

    The North Atlantic Treaty Organization , also called the Atlantic Alliance, is a military alliance established by the signing of the North Atlantic Treaty on 4 April 1949....
     radar and jet interceptors, and investigated by Belgium's military (included photographic evidence). Another famous case from 1986 was the JAL
    Japan Airlines

    , or JAL, is the national airline and flag carrier of Japan. It is one of the largest airline operators in Asia, and is a member of the Oneworld global airline alliance....
     1628 case over Alaska investigated by the FAA.
  • Photographic evidence, including still photos, movie film, and video, including some in the infrared
    Infrared

    Infrared radiation is electromagnetic radiation whose wavelength is longer than that of visible light , but shorter than that of terahertz radiation and microwaves ....
     spectrum (rare).
  • Recorded visual spectrogram
    Spectrogram

    A spectrogram is an image that shows how the spectral density of a signal varies with time. Also known as spectral waterfalls, sonograms, voiceprints, or voicegrams, spectrograms are used to identify phonetics sounds, to analyse the cries of animals, and in the fields of music, sonar/radar, speech processing, seismo...
    s
  • Recorded gravimetric (example
    Project Magnet

    Project Magnet was an unidentified flying object study programme established by the Canada Transport Canada on December 2, 1950, under the direction of Wilbert B....
    ) and magnetic disturbances (extremely rare)
  • Claims of physical trace of landing UFOs, including ground impressions, burned and/or desiccated soil, burned and broken foliage, magnetic anomalies, increased radiation levels, and metallic traces. See, e.g. Height 611 UFO Incident
    Height 611 UFO Incident

    Height 611 UFO incident refers to a Unidentified flying object crash claimed to happen in Dalnegorsk, Primorsky Krai, Soviet Union, on January 29, 1986....
     or the 1964 Lonnie Zamora
    Lonnie Zamora

    Lonnie Zamora is a retired New Mexico police officer who reported a UFO sighting while on duty on Friday, April 24, 1964, near Socorro, New Mexico....
    's Socorro
    Socorro, New Mexico

    Socorro is a city in Socorro County, New Mexico in the U.S. state of New Mexico. It stands in the Rio Grande Valley, at an elevation of 4579 feet ....
    , New Mexico
    New Mexico

    New Mexico is a U. S. State located in the Southwestern United States of the United States. Inhabited by Native Americans in the United States populations for many centuries, it has also has been part of the Spanish Empire viceroyalty of New Spain, part of Mexico, and a U.S....
     encounter of the USAF Project Blue Book
    Project Blue Book

    Project Blue Book was one of a series of systematic studies of Unidentified flying objects conducted by the United States Air Force . Started in 1952, it was the second revival of such a study....
     cases). A well-known example from December 1980 was the USAF Rendlesham Forest Incident
    Rendlesham Forest Incident

    The Rendlesham Forest Incident is the name given to a series of reported sightings of unexplained lights and the alleged landing of an extraterrestrial life spacecraft in Rendlesham Forest, Suffolk, England in late December 1980....
     in England. Another less than two weeks later, in January 1981, occurred in Trans-en-Provence and was investigated by GEPAN
    GEIPAN

    GEIPAN , formerly known as GEPAN and SEPRA , is a unit of the French Space Agency CNES whose brief is to investigate unidentified aerospace phenomena and make its findings available to the public....
    , then France's official government UFO-investigation agency. Project Blue Book
    Project Blue Book

    Project Blue Book was one of a series of systematic studies of Unidentified flying objects conducted by the United States Air Force . Started in 1952, it was the second revival of such a study....
     head Edward J. Ruppelt
    Edward J. Ruppelt

    Edward J. 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....
     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, cornea
    Cornea

    The cornea is the transparency front part of the eye that covers the Iris , pupil, and anterior chamber. Together with the cilliary muscles, the cornea reflects light, and as a result helps the eye to dilate, accounting for approximately two-thirds of the eye's total optical power....
    l burns, and symptoms superficially resembling radiation poisoning
    Radiation poisoning

    Radiation poisoning, also called "radiation sickness" or a "creeping dose", is a form of damage to organ tissue due to excessive exposure to ionizing radiation....
    , such as the Cash-Landrum incident
    Cash-Landrum incident

    The Cash-Landrum Incident was a reported Unidentified Flying Object sighting from the United States in 1980, which the witnesses insist was responsible for damage to their health....
     in 1980. One such case dates back to 1886, a Venezuelan incident reported in Scientific American
    Scientific American

    Scientific American is a popular science science magazine, published since August 28, 1845, making it one of the oldest continuously published magazines in the United States....
     magazine.
  • Animal/cattle mutilation
    Cattle mutilation

    Cattle mutilation is the apparent killing and then mutilation of cattle under unusual or anomalous circumstances. Sheep and horses have been allegedly mutilated under similar circumstances....
     cases, that some feel are also part of the UFO phenomenon. Such cases can and have been analyzed using forensic science techniques.
  • 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
    Crop Circles

    Crop Circles was a collaboration between the psychedelic trance band Etnica and a Milanese group called Lotus Omega . An album, entitled "Tetrahedron", should have been released around 1998, but the project was abandoned because the British label Auracle Recordings went bankrupt....
    )
  • Electromagnetic interference
    Electromagnetic interference

    Electromagnetic interference is an unwanted disturbance that affects an electrical circuit due to either electromagnetic conduction or electromagnetic radiation emitted from an external source....
     (EM) effects, including stalled cars, power black-outs, radio/TV interference, magnetic compass deflections, and aircraft navigation, communication, and engine disruption. A famous 1976 military case
    1976 Tehran UFO Incident

    The 1976 Tehran UFO Incident was a radar and visual sighting of an unidentified flying object over Tehran, the capital of Iran, during the early morning hours of September 19, 1976....
     over Tehran
    Tehran

    Tehran is the capital and largest city of Iran, and the administrative center of Tehran Province. Tehran is a sprawling city at the foot of the Alborz mountain range with an immense network of highways unparalleled in Western Asia....
    , recorded in CIA and DIA
    Defense Intelligence Agency

    The Defense Intelligence Agency, or DIA, is a major producer and manager of military intelligence for the United States Department of Defense, employing over 11,000 military and civilian employees worldwide....
     classified documents, resulted in communication losses in multiple aircraft and weapons system failure in an F-4 Phantom II
    F-4 Phantom II

    The McDonnell Douglas F-4 Phantom II is a two-seat, twin-engined, all-weather, long-range supersonic interceptor jet fighter/fighter-bomber originally developed for the United States Navy by McDonnell Aircraft....
     jet interceptor as it was about to fire a missile on one of the UFOs. This was also a radar/visual case.
  • Remote radiation detection, some noted in FBI and CIA documents occurring over government nuclear installations at Los Alamos National Laboratory
    Los Alamos National Laboratory

    Los Alamos National Laboratory is a United States Department of Energy United States Department of Energy National Labs, managed and operated by Los Alamos National Security, LLC , located in Los Alamos, New Mexico....
     and Oak Ridge National Laboratory
    Oak Ridge National Laboratory

    Oak Ridge National Laboratory is a multiprogram science and technology national laboratory managed for the United States Department of Energy by UT-Battelle....
     in 1950, also reported by Project Blue Book
    Project Blue Book

    Project Blue Book was one of a series of systematic studies of Unidentified flying objects conducted by the United States Air Force . Started in 1952, it was the second revival of such a study....
     director Ed Ruppelt in his book.
  • Actual hard physical evidence cases, such as 1957, Ubatuba
    Ubatuba

    Ubatuba is a Brazilian city, located on the southeast coast, in the state of S?o Paulo . The population in 2003 was 76,847, its density was 107.93 hab/km? and the area is 712 km?....
    , Brazil, magnesium
    Magnesium

    Magnesium is a chemical element with the symbol Mg, atomic number 12, atomic weight 24.3050 and common oxidation number +2.Magnesium, an alkaline earth metal, is the ninth most abundance of the chemical elements in the universe by mass....
     fragments analyzed by the Brazilian government and in the Condon Report and by others. The 1964 Socorro/Lonnie Zamora
    Lonnie Zamora

    Lonnie Zamora is a retired New Mexico police officer who reported a UFO sighting while on duty on Friday, April 24, 1964, near Socorro, New Mexico....
     incident also left metal traces, analyzed by NASA
    NASA

    The National Aeronautics and Space Administration is an agency of the Federal government of the United States, responsible for the nation's public list of space agencies....
    .
  • Angel hair and angel grass, possibly explained in some cases as nests from ballooning spiders
    Ballooning (spider)

    Ballooning is a term used for the mechanical kiting that many spiders, as well as certain mites and some caterpillars use to disperse through the air....
     or chaff
    Chaff (radar countermeasure)

    Chaff, originally called Window by the United Kingdom, and D?ppel by the World War II era Germany Luftwaffe, is a radar countermeasure in which aircraft or other targets spread a cloud of small, thin pieces of aluminium, metallised glass fibre or plastic, which either appears as a cluster of secondary targets on radar screens...
    .


These various reported physical evidence cases have been studied by various scientist and engineers, both privately and in official governmental studies (such as Project Blue Book
Project Blue Book

Project Blue Book was one of a series of systematic studies of Unidentified flying objects conducted by the United States Air Force . Started in 1952, it was the second revival of such a study....
, the Condon Committee
Condon Committee

The Condon Committee was the informal name of the University of Colorado UFO Project, a study of unidentified flying objects, undertaken at the University of Colorado at Boulder from 1966 to 1968 under the direction of physicist Edward Condon....
, and the French GEPAN/SEPRA
GEIPAN

GEIPAN , formerly known as GEPAN and SEPRA , is a unit of the French Space Agency CNES whose brief is to investigate unidentified aerospace phenomena and make its findings available to the public....
). A comprehensive scientific review of physical evidence cases was carried out by the 1998 Sturrock UFO panel.

Ufology

Ufology
Ufology

Ufology is a neologism coined to describe the collective efforts of those who study unidentified flying object reports and associated evidence....
 is a neologism
Neologism

A neologism is a newly coined word that may be in the process of entering common use, but has not yet been accepted into mainstream language . Neologisms are often directly attributable to a specific person, publication, period, or event....
 describing the collective efforts of those who study UFO reports and associated evidence.

UFO researchers


UFO organizations


Reverse engineering

Attempts have been made to reverse engineer
Reverse engineering

Reverse engineering is the process of discovering the technological principles of a device, object or system through analysis of its structure, function and operation....
 the possible physics
Physics

Physics is the natural science which examines basic concepts such as energy, force, and spacetime and all that derives from these, such as mass, charge, matter and its Motion ....
 behind UFOs through analysis of both eyewitness reports and the physical evidence, on the assumption that they are powered vehicles. Examples are former NASA
NASA

The National Aeronautics and Space Administration is an agency of the Federal government of the United States, responsible for the nation's public list of space agencies....
 and nuclear engineer James McCampbell in his book Ufology, NACA
National Advisory Committee for Aeronautics

The National Advisory Committee for Aeronautics was a United States federal agency founded on March 3, 1915 to undertake, promote, and institutionalize aeronautical research....
/NASA
NASA

The National Aeronautics and Space Administration is an agency of the Federal government of the United States, responsible for the nation's public list of space agencies....
 engineer Paul R. Hill
Paul R. Hill

Paul R. Hill was an United States pioneering aeronautical research engineer who spent a lifetime on the cutting edge of research and development for National Advisory Committee for Aeronautics and NASA....
 in his book Unconventional Flying Objects, and German rocketry pioneer Hermann Oberth
Hermann Oberth

Hermann Julius Oberth was a Transylvania born, physicist, and, along with the Russian Konstantin Tsiolkovsky and the United States Robert Goddard , one of the founding fathers of rocketry and astronautics....
. Among subjects tackled by McCampbell, Hill, and Oberth was the question of how UFOs can fly at supersonic
Supersonic

The term supersonic is used to define a speed that is over the speed of sound . At a typical temperature like 21 ?C , the threshold value required for an object to be traveling at a supersonic speed is approximately 344 metre per second, ....
 speeds without creating a sonic boom
Sonic boom

File:Mach cone.svgThe term 'sonic boom' is commonly used to refer to the shocks caused by the supersonic flight of an aircraft. Sonic booms generate enormous amounts of sound energy, sounding much like an explosion....
. McCampbell's proposed solution of a microwave plasma
Microwave plasma

Microwaves, being high frequency electromagnetic radiation in the GHz range, are capable of exciting electrodeless gas discharges.Microwave-excited Plasma s have two appealing properties:...
 parting the air in front of the craft is currently being researched by Dr. Leik Myrabo
Leik Myrabo

Leik Myrabo is an aerospace engineering professor at Rensselaer Polytechnic Institute who has demonstrated the feasibility of using ground-based lasers to propel objects into orbit; possibly reducing orbit-flight costs by a factor of 1000....
, Professor of Engineering Physics at the Rensselaer Polytechnic Institute
Rensselaer Polytechnic Institute

Rensselaer Polytechnic Institute, or RPI, is a Private university research university located in Troy, New York, New York, United States. RPI was founded in 1824 by Stephen Van Rensselaer III for the "application of science to the common purposes of life", and is the oldest technological university in the English-speaking world....
 as a possible advance in hypersonic
Hypersonic

In aerodynamics, hypersonic speeds are speeds that are highly supersonic. Since the 1970s, the term has generally been assumed to refer to speeds of Mach number and above....
 flight. In contrast, Hill and Oberth believed UFOs utilize an as yet unknown anti-gravity
Anti-gravity

Anti-gravity is the idea of creating a place or object that is free from the force of gravity. It does not refer to countering the gravitational force by an opposing force of a different nature, as a helium balloon does; instead, anti-gravity requires that the fundamental causes of the force of gravity be made either not present or not applic...
 field to accomplish the same thing as well as provide propulsion and protection of occupants from the effects of high acceleration.

UFO categorization

Some researchers recommend that observations be classified according to the features of the phenomenon or object that are reported or recorded. Typical categories include:
  • Saucer
    Flying saucer

    Flying saucer is the name given to a type of unidentified flying object with a disc- or saucer-shaped body, usually described as silver or metallic, occasionally reported as covered with running lights or surrounded with a glowing light, hovering or moving rapidly either alone or in tight formations with other similar craft, and exhibiting...
    , toy-top, or disk-shaped "craft" without visible or audible propulsion. (day and night)
  • Large triangular "craft" or triangular light pattern, usually reported at night.
  • Cigar-shaped "craft" with lighted windows (Meteor fireballs are sometimes reported this way, but are very different phenomena).
  • Other: chevrons, (equilateral) triangles, crescent, boomerangs, spheres (usually reported to be shining, glowing at night), domes, diamonds, shapeless black masses, eggs, pyramids and cylinders, classic "lights".


Popular UFO classification systems include the Hynek system
Ufology

Ufology is a neologism coined to describe the collective efforts of those who study unidentified flying object reports and associated evidence....
, created by J. Allen Hynek
J. Allen Hynek

Dr. Josef Allen Hynek was a United States astronomer, professor, and ufology.He is perhaps best remembered for his UFO research: Hynek acted as scientific adviser to UFO studies undertaken by the U.S....
, and the Vallée system
Ufology

Ufology is a neologism coined to describe the collective efforts of those who study unidentified flying object reports and associated evidence....
, created by Jacques Vallée
Jacques Vallée

Jacques F. Vall?e, Ph.D. , is a French-born venture capitalist, computer scientist, ufology and former astronomer, currently residing in San Francisco, California in the United States....
.

Hynek's system involves dividing the sighted object by appearance, subdivided further into the type of "close encounter" (a term from which the film director Steven Spielberg
Steven Spielberg

Steven Allan Spielberg, KBE is an American film director, screenwriter and film producer. Forbes magazine places Spielberg's net worth at $3.1 billion....
 derived the title of his UFO movie, "Close Encounters of the Third Kind").

Jacques Vallée's system classifies UFOs into five broad types, each with from three to five subtypes that vary according to type.

Conspiracy theories

UFOs are sometimes an element of elaborate conspiracy theories in which governments are said to be intentionally covering up the existence of aliens, or sometimes collaborating with them. There are many versions of this story; some are exclusive, while others overlap with various other conspiracy theories.

In the U.S., opinion polls again indicate that a strong majority of people believe the U.S. government is withholding such information. Various notables have also expressed such views. Some examples are astronauts Gordon Cooper
Gordon Cooper

Leroy Gordon Cooper, Jr., also noted as Gordo Cooper, was an United States astronaut. Cooper was one of the Mercury Seven in Project Mercury, the first manned-space effort by the United States....
 and Edgar Mitchell, Senator Barry Goldwater
Barry Goldwater

Barry Morris Goldwater was a five-term United States Senate from Arizona and the History of the United States Republican Party's nominee for President of the United States in the U.S....
, Vice Admiral Roscoe H. Hillenkoetter
Roscoe H. Hillenkoetter

Roscoe Henry Hillenkoetter , born in St. Louis, Missouri, was the third director of the post-WWII U.S. Central Intelligence Group and the first director of the Central Intelligence Agency created by the National Security Act of 1947....
 (the first CIA director), Lord Hill-Norton (former British Chief of Defense Staff and NATO
NATO

The North Atlantic Treaty Organization , also called the Atlantic Alliance, is a military alliance established by the signing of the North Atlantic Treaty on 4 April 1949....
 head), the 1999 high-level French COMETA report by various French generals and aerospace experts, and Yves Sillard (former director of the French space agency CNES
CNES

The is the France government space agency . Its headquarters are located in central Paris. It operates out of the Centre Spatial Guyanais, but also has payloads launched from other space centres operated by other countries....
, new director of French UFO research organization GEIPAN
GEIPAN

GEIPAN , formerly known as GEPAN and SEPRA , is a unit of the French Space Agency CNES whose brief is to investigate unidentified aerospace phenomena and make its findings available to the public....
).

There is also speculation that UFO phenomena are tests of experimental aircraft or advanced weapons. In this case UFOs are viewed as failures to retain secrecy, or deliberate attempts at misinformation: to deride the phenomenon so that it can be pursued unhindered. This explanation may or may not feed back into the previous one, where current advanced military technology is considered to be adapted alien technology (see also: skunk works
Skunk works

Skunk Works is an official alias for Lockheed Martin?s Advanced Development Programs , formerly called Lockheed Advanced Development Projects....
 and Area 51
Area 51

Area 51 is a nickname for a military base located in the southern portion of Nevada in the western United States . Situated at its center, on the southern shore of Groom Lake, is a large secretive military airfield....
).

It has also been suggested by a few paranormal authors that all or most human technology and culture is based on extraterrestrial contact. See also ancient astronauts.

Allegations of evidence suppression

Some also contend regarding physical evidence that it exists abundantly but is swiftly and sometimes clumsily suppressed by governments, aiming to insulate a population they regard as unprepared for the social, theological, and security implications of such evidence. See the Brookings Report
Brookings Report

The Brookings Report or Proposed Studies on the Implications of Peaceful Space Activities for Human Affairs, was commissioned by NASA and created by the Brookings Institution; it was submitted to the United States House of Representatives in the 87th United States Congress on April 18, 1961....
.

There have been allegations of suppression of UFO related evidence for many decades. There are also conspiracy theories which claim that physical evidence might have been removed and/or destroyed/suppressed by some governments. (See also Men in Black
Men in Black

Men in Black , in popular culture, is a term used in UFO conspiracy theory to describe men dressed in black suits claiming to be government agencys who attempt to harass or threaten Unidentified flying object witnesses into silence....
) Some examples are:
  • On July 7, 1947, William Rhodes took photos of an unusual object over Phoenix
    Phoenix, Arizona

    Phoenix is the capital and largest city in the U.S. state of Arizona, as well as the fifth most populous city in the United States. Phoenix is home to 1,552,259 residents, and is the anchor of the Phoenix Metropolitan Area with 4,179,427 residents....
    , Arizona
    Arizona

    The State of Arizona is a U.S. state located in the Southwestern United States of the United States. The capital and largest city is Phoenix, Arizona....
    . The photos appeared in a Phoenix newspaper and a few other papers. According to documents from Project Bluebook, an Army counter-intelligence (CIC) agent and an FBI agent interviewed Rhodes on August 29 and convinced him to surrender the negatives. The CIC agent deliberately concealed his true identity, leaving Rhodes to believe both men were from the FBI. Rhodes said he wanted the negatives back, but when he turned them into the FBI the next day, he was informed he wouldn't be getting them back, though Rhodes later tried unsuccessfully. The photos were extensively analyzed and would eventually show up in some classified Air Force UFO intelligence reports. (Randle, 34–45, full account)
  • A June 27, 1950, movie of a "flying disk" over Louisville
    Louisville, Kentucky

    Louisville is Kentucky's largest city and county seat of Jefferson County, Kentucky. The city's estimated population as of 2006 is listed as 557,789, with a population of 1,233,733 in the Louisville-Jefferson County, KY-IN Metropolitan Statistical Area....
    , Kentucky
    Kentucky

    The Commonwealth of Kentucky is a U.S. state located in the East Central United States of America. Kentucky is normally included in the group of Southern United States , but it is uncommonly included, geographically and culturally, in the Midwestern United States....
    , taken by a Louisville Courier-Journal photographer, had the USAF Directors of counterintelligence (AFOSI
    Air Force Office of Special Investigations

    The Air Force Office of Special Investigations , is a List of United States Air Force Field Operating Agencies of the United States Air Force that provides professional investigative services to commanders throughout the Air Force....
    ) and intelligence discussing in memos how to best obtain the movie and interview the photographer without revealing Air Force interest. One memo suggested the FBI be used, then precluded the FBI getting involved. Another memo said "it would be nice if OSI could arrange to secure a copy of the film in some covert manner," but if that wasn't feasible, one of the Air Force scientists might have to negotiate directly with the newspaper. In a recent interview, the photographer confirmed meeting with military intelligence and still having the film in his possession until then, but refused to say what happened to the film after that.
  • In another 1950 movie incident from Montana, Nicholas Mariana filmed some unusual aerial objects and eventually turned the film over to the U.S. Air Force, but insisted that the first part of the film, clearly showing the objects as spinning discs, had been removed when it was returned to him. (Clark, 398)
  • During the military investigation of green fireballs
    Green Fireballs

    Green Fireballs is a self-descriptive term used to refer to certain unidentified flying objects which have been sighted in the sky since the late 1940s....
     in New Mexico
    New Mexico

    New Mexico is a U. S. State located in the Southwestern United States of the United States. Inhabited by Native Americans in the United States populations for many centuries, it has also has been part of the Spanish Empire viceroyalty of New Spain, part of Mexico, and a U.S....
    , UFOs were photographed by a tracking camera over White Sands Proving Grounds on April 27, 1949. The final report in 1951 on the green fireball investigation claimed there was insufficient data to determine anything. However, documents later uncovered by Dr. Bruce Maccabee
    Bruce Maccabee

    Bruce Maccabee is an United States optical physicist employed by the U.S. Navy, and a leading ufologist....
     indicate that triangulation
    Triangulation

    In trigonometry and geometry, triangulation is the process of determining the location of a point by measuring angles to it from known points at either end of a fixed baseline, rather than measuring distances to the point directly....
     was accomplished. The data reduction and photographs showed four objects about 30 feet in diameter flying in formation at high speed at an altitude of about 30 miles. Maccabee says this result was apparently suppressed from the final report.
  • Project Blue Book
    Project Blue Book

    Project Blue Book was one of a series of systematic studies of Unidentified flying objects conducted by the United States Air Force . Started in 1952, it was the second revival of such a study....
     director Edward J. Ruppelt
    Edward J. Ruppelt

    Edward J. 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....
     reported that, in 1952, a U.S. Air Force pilot fired his jet's machine guns at a UFO, and that the official report which should have been sent to Blue Book was quashed.
  • Astronaut
    Astronaut

    An astronaut or cosmonaut is a person trained by a List of human spaceflight programs to command, pilot, or serve as a crew member of a spacecraft....
     Gordon Cooper
    Gordon Cooper

    Leroy Gordon Cooper, Jr., also noted as Gordo Cooper, was an United States astronaut. Cooper was one of the Mercury Seven in Project Mercury, the first manned-space effort by the United States....
     reported suppression of a flying saucer movie filmed in high clarity by two Edwards AFB range photographers on May 3, 1957. Cooper said he viewed developed negatives of the object, clearly showing a dish-like object with a dome on top and something like holes or ports in the dome. The photographers and another witness, when later interviewed by Dr. James McDonald
    James E. McDonald

    James E. McDonald was an United States physicist. He is best known for his research regarding unidentified flying object. McDonald was senior physicist at the Institute for Atmospheric Physics and professor in the Department of Meteorology, University of Arizona, Tucson....
    , confirmed the story. Cooper said military authorities then picked up the film and neither he nor the photographers ever heard what happened to it. The incident was also reported in a few newspapers, such as the Los Angeles Times
    Los Angeles Times

    The Los Angeles Times is a daily newspaper published in Los Angeles, California and distributed throughout the Western United States. It is the second-largest metropolitan newspaper in the United States and the fourth-most widely distributed newspaper in the United States....
    . The official explanation, however, was that the photographers had filmed a weather balloon distorted by hot desert air.
  • On January 22, 1958, when NICAP director Donald Keyhoe
    Donald Keyhoe

    Donald Edward Keyhoe was an United States United States Marine Corps officer with some flight experience, writer of many aviation articles and stories in a variety of leading publications, and manager of the promotional tours of aviation pioneers, especially of Charles Lindbergh....
     appeared on CBS television, his statements on UFOs were pre-censored by the Air Force. During the show when Keyhoe tried to depart from the censored script to "reveal something that has never been disclosed before," CBS cut the sound, later stating Keyhoe was about to violate "predetermined security standards" and about to say something he wasn't "authorized to release." What Keyhoe was about to reveal were four publicly unknown military studies concluding UFOs were interplanetary (including the 1948 Project Sign
    Project Sign

    Project Sign was an official U.S. government study of unidentified flying objects undertaken by the United States Air Force in late 1947 and dissolved in late 1948....
     Estimate of the Situation
    Estimate of the Situation

    The Estimate of the Situation was a document supposedly written in 1948 by the personnel of United States Air Force's Project Sign -including the project?s director, Captain Robert R....
     and Blue Book's 1952 engineering analysis of UFO motion). (Good, 286–287; Dolan 293–295)
  • Astronomer Jacques Vallee
    Jacques Vallée

    Jacques F. Vall?e, Ph.D. , is a French-born venture capitalist, computer scientist, ufology and former astronomer, currently residing in San Francisco, California in the United States....
     reported that in 1961 he witnessed the destruction of the tracking tapes of unknown objects orbiting the Earth. (However, Vallee indicated that this didn't happen because of government pressure but because the senior astronomers involved didn't want to deal with the implications.)
  • In 1965, Rex Heflin took four Polaroid
    Instant camera

    The instant camera is a type of camera with instant film. The most famous are those made by the Polaroid Corporation. Polaroid no longer manufactures such cameras....
     photos of a hat-shaped object. Two years later (1967), two men posing as NORAD agents confiscated three prints. Just as mysteriously, the photos were returned to his mailbox in 1993.
  • A March 1, 1967 memo directed to all USAF divisions, from USAF Lt. General Hewitt Wheless, Assistant Vice Chief of Staff, stated that unverified information indicated that unknown individuals, impersonating USAF officers and other military personnel, had been harassing civilian UFO witnesses, warning them not to talk, and also confiscating film, referring specifically to the Heflin incident. AFOSI was to be notified if any personnel were to become aware of any other incidents. (Document in Fawcett & Greenwood, 236).
  • John Callahan, former Division Chief of the Accidents and Investigations Branch of the FAA, Washington D.C., also a Disclosure Project witness, said that following a 1986 encounter of a Japanese airlines 747 with a giant UFO over Alaska, recorded by air and ground radar, the FAA conducted an investigation. Callahan held a briefing a few days later for President Reagan's Scientific Study Group, the FBI, and CIA. After the briefing, one of the CIA agents told everybody they "were never there and this never happened," adding they were fearful of public panic.
  • In 1996, the CIA revealed an instance from 1964 where two CIA agents posed as USAF representatives in order to recover a film canister from a Corona spy satellite
    Corona (satellite)

    Corona was a United States military reconnaissance satellite system operated by the CIA Directorate of Science & Technology with substantial assistance from the US Air Force, used for photographic surveillance of the Soviet Union, China and other areas from June 1959 until May 1972....
     that had accidentally come down in Venezuela
    Venezuela

    Venezuela , officially the Bolivarian Republic of Venezuela , is a country on the northern coast of South America.The country comprises a continental mainland and numerous islands located off the Venezuelan coastline in the Caribbean Sea....
    . The event was then publicly dismissed as an unsuccessful NASA
    NASA

    The National Aeronautics and Space Administration is an agency of the Federal government of the United States, responsible for the nation's public list of space agencies....
     space experiment.


Famous hoaxes

  • The Maury Island Incident
    Maury Island incident

    The Maury Island Incident is said to be an early modern unidentified flying object Close encounter, which allegedly took place in June 1947, three days before the famous sighting by Kenneth Arnold, widely considered the original encounter with flying saucers....
  • The Ummo
    Ummo

    Ummo or Ummoism describes a series of decades-long claims that extraterrestrial life from the planet Ummo were communicating with persons on the earth....
     affair, a decades-long series of detailed letters and documents allegedly from extraterrestrials. The total length of the documents is at least 1000 pages, and some estimate that further undiscovered documents may total nearly 4000 pages. A Jose Luis Jordan Pena came forward in the early nineties claiming responsibility for the phenomenon, and most consider there to be little reason to challenge his claims.
  • George Adamski
    George Adamski

    George Adamski was a Polish-born American citizen who became widely known in ufology circles, and to some degree in popular culture, after he claimed to have photographed ships from other planets, met with friendly "Space Brothers", and to have taken flights with them....
     over the space of two decades made various claims about his meetings with telepathic aliens from nearby planets. He claimed that photographs of the far side of the moon taken by a Soviet orbital probe in 1959 were fake, and that there were cities, trees and snow-capped mountains on the far side of the moon.
  • In 1987/1988 Ed Walters allegedly perpetrated a hoax in Gulf Breeze
    Gulf Breeze, Florida

    Gulf Breeze is a city located on the Fairpoint Peninsula in Santa Rosa County, Florida, United States and is a suburb of Pensacola, Florida which lies to the north, across Pensacola Bay....
    , Florida
    Florida

    Florida is a U.S. state located in the Southeastern United States of the United States, bordering Alabama to the northwest and Georgia to the northeast....
    . Walters claimed at first having seen a small UFO flying near his home, and then in a second incident seeing the same UFO and a small alien being standing by his back door after being alerted by his dog. Several photographs were taken of the craft, but none of the being. Three years later, in 1990, after the Walters family had moved, the new residents discovered a model of a UFO poorly hidden in the attic that bore an undeniable resemblance to the craft in Walters' photographs. Various witnesses and detractors came forward after the local Pensacola
    Pensacola

    Pensacola is the name of several cities as well as other things:* Pensacola , a group of Native Americans of the United States* A number of places in the U.S....
     newspaper printed a story about the discovered model, and some investigators now consider the sightings to be a hoax. In addition, a six-figure television miniseries and book deal were nearly struck with Walters.
  • Warren William (Billy) Smith, A popular writer and confessed hoaxster.


Not all Ufologists who have studied some these cases agree they are hoaxes. One notable example, Naval optical physicist Dr. Bruce Maccabee
Bruce Maccabee

Bruce Maccabee is an United States optical physicist employed by the U.S. Navy, and a leading ufologist....
 extensively investigated the Ed Walters Gulf Breeze case, analyzed the various photos and videos, and deemed them authentic. In fact, some of the details would have required extensive expertise to fake. Maccabee also noted there were many independent witnesses to some of the Gulf Breeze sightings besides Walters, including Maccabee himself.

UFOs in popular culture

UFOs constitute a widespread international cultural
Popular culture

Popular culture is the totality of Distinction memes, ideas, Perspective s and Attitude s that are deemed preferred per an informal consensus within the mainstream of a given culture....
 phenomenon of the last half-century. Gallup poll
Gallup poll

The Gallup Poll is the division of The Gallup Organization that regularly conducts public opinion polls in the United States and more than 140 countries around the world....
s rank UFOs near the top of lists for subjects of widespread recognition. In 1973, a survey found that 95 percent of the public reported having heard of UFOs, whereas only 92 percent had heard of US President
President of the United States

The President of the United States is the head of state and head of government of the United States and is the highest political official in the United States by influence and recognition....
 Gerald Ford
Gerald Ford

Gerald Rudolph Ford, Jr. was the List of Presidents of the United States President of the United States, serving from 1974 to 1977, and the List of Vice Presidents of the United States Vice President of the United States serving from 1973 to 1974....
 in a 1977 poll taken just nine months after he left the White House
White House

The White House is the official residence and principal workplace of the President of the United States. Located at 1600 Pennsylvania Avenue in Washington, D.C., it was built between 1792 and 1800 of white-painted Aquia sandstone in the late Georgian architecture and has been the executive residence of every U.S....
. (Bullard, 141) A 1996 Gallup poll
Gallup poll

The Gallup Poll is the division of The Gallup Organization that regularly conducts public opinion polls in the United States and more than 140 countries around the world....
 reported that 71 percent of the United States population believed that the government was covering up information regarding UFOs. A 2002 Roper poll for the Sci Fi channel
Sci Fi Channel (United States)

Sci Fi Channel, often stylized SCI FI Channel, is an American cable television channel, launched on September 24, 1992, that specializes in science fiction, fantasy, horror film, and paranormal programming....
 found similar results, but with more people believing UFOs were extraterrestrial craft. In that latest poll, 56 percent thought UFOs were real craft and 48 percent that aliens had visited the Earth. Again, about 70 percent felt the government was not sharing everything it knew about UFOs or extraterrestrial life. Another effect of the flying saucer type of UFO sightings has been Earth-made flying saucer craft in space fiction, for example the Earth-made craft Starship C-57D
Starship C-57D

Starship C-57D is the fictional flying saucer starship, first presented in the 1956 science fiction movie Forbidden Planet....
 in Forbidden Planet
Forbidden Planet

Forbidden Planet is a 1956 in film science fiction film directed by Fred M. Wilcox and starring Walter Pidgeon, Anne Francis and Leslie Nielsen....
, and the saucer part of the USS Enterprise
USS Enterprise

USS Enterprise may refer to the following specific vessels:...
 in Star Trek
Star Trek

Star Trek is an American Science fiction on television entertainment series and media franchise. The Star Trek fictional universe created by Gene Roddenberry is the setting of six television series including the original 1966 Star Trek: The Original Series, in addition to ten feature films with Star Trek to be released on May 8,...
 And many others. For an excellent analysis of the interrelationship between popular culture and UFOs consult the research by psychologist Armando Simon, especially his contribution in Richard Haines' book, UFO Phenomena and the Behavioral Scientist.

Use in film and television

  • See List of major UFO film and television shows


Use in Music

  • See Ufoetry
    Ufoetry

    UFOetry is an organization in Los Angeles, California, dedicated to educating the public about the UFO phenomena and its implications on society....


See also

  • Abduction phenomenon
    Abduction phenomenon

    The term "abduction phenomenon" refers to claims of ordinary people that non-human creatures kidnapped and temporarily removed them from familiar terrestrial surroundings....
  • Ball lightning
    Ball lightning

    Ball lightning may be an atmospheric electricity phenomenon, the physical nature of which is still controversial. The term refers to reports of luminous, usually spherical objects which vary from pea-sized to several meters in diameter....
  • Black triangle (UFO)
  • Bob Lazar
    Bob Lazar

    Robert Scott Lazar , or Bob Lazar, claims to have worked from 1988 until 1989 as a physicist at an area called S-4 , located near Groom Lake, Nevada, next to Area 51....
  • Brookings Report
    Brookings Report

    The Brookings Report or Proposed Studies on the Implications of Peaceful Space Activities for Human Affairs, was commissioned by NASA and created by the Brookings Institution; it was submitted to the United States House of Representatives in the 87th United States Congress on April 18, 1961....
  • Carl Sagan
    Carl Sagan

    Carl Edward Sagan, Ph.D. was an United States astronomer, Astrochemistry, author, and highly successful popularizer of astronomy, astrophysics and other natural sciences....
  • Cattle mutilation
    Cattle mutilation

    Cattle mutilation is the apparent killing and then mutilation of cattle under unusual or anomalous circumstances. Sheep and horses have been allegedly mutilated under similar circumstances....
  • Chicago O'Hare UFO sighting 2006
  • Condon Report
  • Contactees
    Contactees

    Contactees are persons who claim to have experienced contact with extraterrestrial life. Contactees have typically reported that they were given messages or profound wisdom by extraterrestrial beings, and that they were compelled to share these messages....
  • Crop circle
    Crop circle

    Crop circles are patterns created by the flattening of Crop such as wheat, barley, rapeseed , rye, maize, linseed and soy.The term was first used by researcher Colin Andrews to describe simple circles he was researching....
  • Extraterrestrial life
    Extraterrestrial life

    Extraterrestrial life is defined as life which does not originate from Earth. It is the subject of astrobiology and its existence remains hypothetical, because there is no credible evidence of extraterrestrial life which has been generally accepted by the mainstream scientific community....
  • Flying rod
  • Foo fighter
    Foo fighter

    The term foo fighter was used by Allies aircraft aircraft pilot in World War II to describe various unidentified flying object or mysterious aerial phenomena seen in the skies over both the European Theater of Operations and Pacific Theater of Operations....
  • Forteana
  • Hessdalen light
    Hessdalen light

    Hessdalen Lights are unexplained lights usually seen in the valley of Hessdalen, Norway.These lights are well known and have been recorded and studied by physicists....
  • Jacques Vallée
    Jacques Vallée

    Jacques F. Vall?e, Ph.D. , is a French-born venture capitalist, computer scientist, ufology and former astronomer, currently residing in San Francisco, California in the United States....
  • John Keel
    John Keel

    John Alva Keel is a Fortean author and professional journalist currently residing in New York City, New York, USA.John Keel's first published story was in a magician's magazine at the age of 12....
  • Kenneth Arnold
    Kenneth Arnold

    Kenneth A. Arnold was an American businessman and pilot.He is best-known for making what is generally considered the first widely reported unidentified flying object sighting in the United States, after claiming to see nine unusual objects flying in a chain near Mount Rainier, Washington on June 24, 1947....
  • Kodiak Island UFO, 2007
    Kodiak Island UFO, 2007

    The Kodiak Island UFO, 2007 concerns a multi-witness sighting of a flaming UFO over the Kenai Peninsula and Kodiak, Alaska on 25 September 2007....
  • List of U.S. paranormal travel books
  • Magazines of anomalous phenomena
    List of magazines of anomalous phenomena

    This is a list of magazines on anomalous and Charles Fort phenomena....
  • Mutual UFO Network
    Mutual UFO Network

    The Mutual UFO Network, or MUFON, is one of the oldest and largest Unidentified flying object investigative organizations in the United States....
  • Ralph Horton flying saucer crash
    Ralph Horton flying saucer crash

    The Ralph Horton flying saucer crash refers to a Identified flying object that crashed on the farm of Ralph Horton in Fulton County, Georgia, in July 1952....
  • Robertson Panel
    Robertson Panel

    The Robertson Panel was a committee commissioned by the Central Intelligence Agency in 1952 in response to widespread reports of unidentified flying objects, especially in the Washington, D.C....
  • Roswell incident
  • Stanton T. Friedman
    Stanton T. Friedman

    Stanton Terry Friedman is a professional ufology, currently residing in Fredericton, New Brunswick, Canada. He is the original civilian investigator of the Roswell incident....
  • Scientific skepticism
    Scientific skepticism

    Scientific skepticism or rational skepticism , sometimes referred to as skeptical inquiry, is a scientific or practical, epistemology position in which one questions the veracity of claims lacking empirical evidence....
  • The Disclosure Project
    The Disclosure Project

    The Disclosure Project is an organization started by Steven M. Greer in 1993, which alleges a conspiracy theory of information relating to unidentified flying objects ....
  • UFOs in fiction
    UFOs in fiction

    Many works of fiction have featured Unidentified flying object. In most cases, as the fictional story progresses, the Earth is being invaded by hostile alien forces from outer space, usually from Mars, as depicted in early science fiction, or the people are being destroyed by alien forces, as depicted in the film Independence Day ....
  • Unidentified submerged object
    Unidentified submerged object

    An unidentified submerged object, or USO, is any object or optical or mechanical detection phenomenon of unknown origin observed under water that remains unidentified even after thorough investigation....
  • Unusual ground marking
    Unusual Ground Marking

    Unusual ground markings or UGMs are ground features that appear to be hard to explain. The best-known UGMs are crop circles.Other forms of UGM are ice circles, footprints of unknown origin and burnt grass....
  • Valentich Disappearance
    Valentich Disappearance

    The Frederick Valentich Disappearance is an event that occurred on October 21, 1978, in which 20-year-old Frederick Valentich Missing person in unexplained circumstances while piloting a Cessna 182L light aircraft over Bass Strait to King Island , Australia....
  • Westall High School UFO
    Westall High School UFO

    The Westall UFO encounter is an event claimed to have occurred on 6 April 1966 in Melbourne, Victoria , Australia. Around 11.00 am, for about 20 minutes, more than 200 students and teachers at two Victorian state schools allegedly witnessed an unexplained flying object that descended into a nearby open wild grass field....


  • General
    • Thomas E. Bullard
      Thomas E. Bullard

      Thomas Eddie Bullard is an American folklorist best known for his research into UFOs and the abduction phenomenon. His articles have been published in the Journal of American Folklore and the Journal of UFO Studies, among other journals....
      , "UFOs: Lost in the Myths", pages 141–191 in "UFOs, the Military, and the Early Cold War Era", pages 82–121 in "UFOs and Abductions: Challenging the Borders of Knowledge" David M. Jacobs, editor; 2000, University Press of Kansas, ISBN 0-7006-1032-4
    • Jerome Clark
      Jerome Clark

      Jerome Clark is an United States researcher and writer, specializing in unidentified flying objects and other anomalous phenomena; he is also a songwriter of some note....
      , The UFO Book: Encyclopedia of the Extraterrestrial, 1998, Visible Ink Press, ISBN 1-57859-029-9. Many classic cases and UFO history provided in great detail; highly documented.*Curran, Douglas. In Advance of the Landing: Folk Concepts of Outer Space. (revised edition), Abbeville Press, 2001. ISBN 0-7892-0708-7. Non-sensational but fair treatment of contemporary UFO legend and lore in N. America, including the so-called "contactee cults." The author traveled the United States with his camera and tape recorder and directly interviewed many individuals.
    • Hall, Richard H., editor. The UFO Evidence: Volume 1. 1964, NICAP, reissued 1997, Barnes & Noble Books, ISBN 0-7607-0627-1. Well-organized, exhaustive summary and analysis of 746 unexplained NICAP cases out of 5000 total cases — a classic.
    • Hall, Richard H. The UFO Evidence: A Thirty-Year Report. Scarecrow Press, 2001. ISBN 0-8108-3881-8. Another exhaustive case study, more recent UFO reports.
    • Hendry, Alan. The UFO Handbook: A Guide to Investigating, Evaluating, and Reporting UFO Sightings. New York: Doubleday & Co., 1979. ISBN 0-385-14348-6. Skeptical but balanced analysis of 1300 CUFOS UFO cases.
    • Hynek, J. Allen
      J. Allen Hynek

      Dr. Josef Allen Hynek was a United States astronomer, professor, and ufology.He is perhaps best remembered for his UFO research: Hynek acted as scientific adviser to UFO studies undertaken by the U.S....
      . The UFO Experience: A scientific inquiry. Henry Regnery Co., 1972.
    • Hynek, J. Allen. The Hynek UFO Report. New York: Barnes & Noble Books, 1997. ISBN 0-7607-0429-5. Analysis of 640 high-quality cases through 1969 by UFO legend Hynek.
    • Rose, Bill and Buttler, Tony. Flying Saucer Aircraft (Secret Projects). Leicester, UK: Midland Publishing, 2006. ISBN 1-85780-233-0.
    • Sagan, Carl
      Carl Sagan

      Carl Edward Sagan, Ph.D. was an United States astronomer, Astrochemistry, author, and highly successful popularizer of astronomy, astrophysics and other natural sciences....
       & Page. Thornton, editors. UFOs: A Scientific Debate. \Cornell University Press, 1996. ISBN 0-7607-0192-2. Pro and con articles by scientists, mostly to the skeptical side.
    • Sheaffer, Robert
      Robert Sheaffer

      Robert Sheaffer , is a freelance writer and a prominent investigator of unidentified flying objects, Christianity, feminism, and many other subjects....
       The UFO Verdict: Examining the Evidence, 1986, Prometheus Books
      Prometheus Books

      Prometheus Books is a publishing company founded in August 1969 by Paul Kurtz, who also founded the Council for Secular Humanism and co- founded Committee for Skeptical Inquiry....
       ISBN 0-87975-338-2
    • Sheaffer, Robert
      Robert Sheaffer

      Robert Sheaffer , is a freelance writer and a prominent investigator of unidentified flying objects, Christianity, feminism, and many other subjects....
       UFO Sightings: The Evidence, 1998, Prometheus Books, ISBN 1-57392-213-7 (revised edition of The UFO Verdict)
    • Sturrock, Peter A.
      Peter A. Sturrock

      Peter Andrew Sturrock is a United Kingdom scientist.An emeritus professor of applied physics at Stanford University, much of Sturrock's career has been devoted to astrophysics, plasma physics, and solar physics, but Sturrock is interested in other fields, including ufology, scientific inference and in the history of science and philosophy...
       (1999). The UFO Enigma: A New Review of the Physical Evidence. New York: Warner Books. ISBN 0-446-52565-0
    • , a virtual museum exhibition at Library and Archives Canada

    Skepticism

    • Philip Plait
      Philip Plait

      Dr. Philip C. Plait is an astronomer and skeptic who runs the website BadAstronomy.com. He formerly worked at the physics and astronomy department at Sonoma State University....
       (2002). Bad Astronomy: Misconceptions and Misuses Revealed, from Astrology to the Moon Landing "Hoax". John Wiley & Sons
      John Wiley & Sons

      John Wiley & Sons, Inc., also referred to as Wiley, is a global publishing company that markets its products to professionals and consumers, students and instructors in higher education, and researchers and practitioners in scientific, technical, medical, and scholarly fields....
      , ISBN 0-471-40976-6. (Chapter 20: Misidentified Flying Objects: UFOs and Illusions of the Mind and Eye.)
    • Ian Ridpath
      Ian Ridpath

      Ian Ridpath is an England science writer and broadcaster made famous for his investigation and explanation of the Rendlesham Forest Incident of December 1980....
       "Astronomical Causes of UFOs"
    • Michael A. Seeds. (1995). Horizons: Exploring the Universe, Wadsworth Publishing, ISBN 0-534-24889-6 and ISBN 0-534-24890-X. (Appendix A)


    Psychology
    • Carl G. Jung, "Flying Saucers: A Modern Myth of Things Seen in the Skies" (translated by R.F.C. Hull); 1979, Princeton University Press, ISBN 0-691-01822-7
    • Armando Simon,A Nonreactive, Quantitative Study of Mass Behavior with Emphasis on the Cinema as Behavior Catalyst," Psychological Reports, 1981, 48, 775-785.
    • Richard Haines"UFO Phenomena and the Behavioral Scientist." Metuchen: Scarecrow Press, 1979.
    • Armando Simon "UFOs: Testing for the Existence of Air Force Censorship." Psychology, 1976, 13, 3-5.
    • Armando Simon "Psychology and the UFOs." The Skeptical Inquirer. 1984, 8, 355-367.

    Histories
    • Richard M. Dolan, UFOs and the National Security State: An Unclassified History, Volume One: 1941–1973, 2000, Keyhole Publishing, ISBN 0-9666885-0-3. Dolan is a professional historian.
    • Downes, Jonathan Rising of the Moon. 2nd ed. Bangor: Xiphos, 2005.
    • Lawrence Fawcett & Barry J. Greenwood, The UFO Cover-Up (Originally Clear Intent), 1992, Fireside Books (Simon & Schuster), ISBN 0-671-76555-8. Many UFO documents.
    • Timothy Good
      Timothy Good

      Timothy Good is a British Ufology and professional violinist.He was born in London and educated at The King's School, Canterbury, Canterbury before being granted a scholarship to the Royal Academy of Music, where he studied the violin....
      ,
      Above Top Secret, 1988, William Morrow & Co., ISBN 0-688-09202-0. Many UFO documents.
    • Timothy Good
      Timothy Good

      Timothy Good is a British Ufology and professional violinist.He was born in London and educated at The King's School, Canterbury, Canterbury before being granted a scholarship to the Royal Academy of Music, where he studied the violin....
      ,
      Need to Know: UFOs, the Military, and Intelligence, 2007, Pegasus Books, ISBN 978-1-933648-38-5. Update of Above Top Secret with new cases and documents
    • Bruce Maccabee
      Bruce Maccabee

      Bruce Maccabee is an United States optical physicist employed by the U.S. Navy, and a leading ufologist....
      ,
      UFO FBI Connection, 2000, Llewellyn Publications, ISBN 1-56718-493-6
    • Kevin Randle, Project Blue Book Exposed, 1997, Marlowe & Company, ISBN 1-56924-746-3
    • Edward J. Ruppelt
      Edward J. Ruppelt

      Edward J. 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....
      ,
      The Report On Unidentified Flying Objects, 1956, Doubleday & Co. . A UFO classic by insider Ruppelt, the first head of the USAF Project Blue Book
      Project Blue Book

      Project Blue Book was one of a series of systematic studies of Unidentified flying objects conducted by the United States Air Force . Started in 1952, it was the second revival of such a study....
    • LeRoy F. Pea, Government Involvement in the UFO Coverup, or earlier title History of UFO Crash/Retrievals", 1988, PEA RESEARCH.


    Technology
    • Paul R. Hill
      Paul R. Hill

      Paul R. Hill was an United States pioneering aeronautical research engineer who spent a lifetime on the cutting edge of research and development for National Advisory Committee for Aeronautics and NASA....
      , Unconventional Flying Objects: a scientific analysis, 1995, Hampton Roads Publishing Co., ISBN 1-57174-027-9. Analysis of UFO technology by pioneering NACA
      NACA

      NACA may refer to:*Neighborhood Assistance Corporation of America a non-profit community advocacy and homeownership organization helping victims of predatory mortgages....
      /NASA
      NASA

      The National Aeronautics and Space Administration is an agency of the Federal government of the United States, responsible for the nation's public list of space agencies....
       aerospace engineer.
    • James M. McCampbell, Ufology: A Major Breakthrough in the Scientific Understanding of Unidentified Flying Objects, 1973, 1976, Celestial Arts, ISBN 0-89087-144-2 . Another analysis by former NASA and nuclear engineer.
    • James M. McCampbell, Physical effects of UFOs upon people, 1986, .
    • Antonio F. Rullán, Odors from UFOs: Deducing Odorant Chemistry and Causation from Available Data, 2000, .
    • Jack Sarfatti, "Super Cosmos", 2005 (Authorhouse)
    • See also the
    • See also the


    External links

    • Ministry of Defence
      Ministry of Defence (United Kingdom)

      The Ministry of Defence is the Departments of the United Kingdom Government responsible for implementation of government defence policy and is the headquarters of the British Armed Forces....