Unidentified flying object

Unidentified flying object

Overview

A term originally coined by the military, an unidentified flying object (usually abbreviated to UFO or U.F.O.) is an unusual apparent anomaly in the sky that is not readily identifiable to the observer as any known object. While a small percentage remain unexplained, the majority of UFO sightings are often later identified as any number of various natural phenomenon or man-made objects.


While technically a UFO refers to any unidentified flying object, in modern popular culture the term UFO has generally become synonymous with alien spacecraft.
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A term originally coined by the military, an unidentified flying object (usually abbreviated to UFO or U.F.O.) is an unusual apparent anomaly in the sky that is not readily identifiable to the observer as any known object. While a small percentage remain unexplained, the majority of UFO sightings are often later identified as any number of various natural phenomenon or man-made objects.

Extraterrestrial hypothesis



While technically a UFO refers to any unidentified flying object, in modern popular culture the term UFO has generally become synonymous with alien spacecraft. Proponents argue that because these objects appear to be technological and not natural phenomenon, and are alleged to display flight characteristics or have shapes seemingly unknown to conventional technology, the conclusion is then that they must not be from Earth. Though UFO sightings have occurred throughout recorded history, modern interest in them dates from World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

 (see foo fighter
Foo fighter
The term foo fighter was used by Allied aircraft pilots in World War II to describe various UFOs or mysterious aerial phenomena seen in the skies over both the European and Pacific Theater of Operations....

), further fueled in the late 1940s by Kenneth Arnold
Kenneth Arnold
Kenneth A. Arnold was an American aviator and businessman. 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 have seen nine unusual objects flying in a chain near Mount Rainier, Washington...

's coining of the term flying saucer
Flying saucer
A flying saucer is a type of unidentified flying object sometimes believed to be of alien origin 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...

 and the Roswell UFO Incident
Roswell UFO incident
The Roswell UFO Incident was the recovery of an object that crashed in the general vicinity of Roswell, New Mexico, in June or July 1947, allegedly an extra-terrestrial spacecraft and its alien occupants. Since the late 1970s the incident has been the subject of intense controversy and of...

. Since then governments have investigated UFO reports, often from a military perspective- and UFO researchers have investigated, written about, and created organizations devoted to the subject. One such investigation, The UK's Project Condign
Project Condign
Project Condign was the name given to a secret UFO study undertaken by the British Government's Defence Intelligence Staff between 1997 and 2000...

 report, notes that Russian, Former Soviet Republics, and Chinese authorities have made a co-ordinated effort to understand the UFO topic and that State military organizations, particularly in Russia, have done "considerably more work (than is evident from open sources)" on military applications which have stemmed from their UFO research. The report also noted that "several aircraft have been destroyed and at least four pilots have been killed 'chasing UFOs'."

Official White House Position


In November 2011, 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 NW in Washington, D.C., the house was designed by Irish-born James Hoban, and built between 1792 and 1800 of white-painted Aquia sandstone in the Neoclassical...

 released an official response to two petitions asking the U.S. government to acknowledge formally that aliens have visited Earth and to disclose any intentional withholding of government interactions with extraterrestrial beings. According to the response, "The U.S. government has no evidence that any life exists outside our planet, or that an extraterrestrial presence has contacted or engaged any member of the human race." Also, according to the response, there is "no credible information to suggest that any evidence is being hidden from the public's eye." The response further noted that efforts, like SETI
SETI
The search for extraterrestrial intelligence is the collective name for a number of activities people undertake to search for intelligent extraterrestrial life. Some of the most well known projects are run by the SETI Institute. SETI projects use scientific methods to search for intelligent life...

, the Kepler space telescope and the NASA Mars rover
Mars Science Laboratory
The Mars Science Laboratory is a National Aeronautics and Space Administration mission with the aim to land and operate a rover named Curiosity on the surface of Mars. The MSL was launched November 26, 2011, at 10:02 EST and is scheduled to land on Mars at Gale Crater between August 6 and 20, 2012...

, continue looking for signs of life
Life
Life is a characteristic that distinguishes objects that have signaling and self-sustaining processes from those that do not, either because such functions have ceased , or else because they lack such functions and are classified as inanimate...

. The response noted "odds are pretty high" that there may be life on other planets but "the odds of us making contact with any of them—especially any intelligent ones—are extremely small, given the distances involved."

Studies


Studies have established that the majority of UFO observations are misidentified conventional objects or natural phenomenon— most commonly aircraft, balloons, noctilucent cloud
Noctilucent cloud
Night clouds or Noctilucent clouds are tenuous cloud-like phenomena that are the "ragged-edge" of a much brighter and pervasive polar cloud layer called polar mesospheric clouds in the upper atmosphere, visible in a deep twilight. They are made of crystals of water ice. The name means roughly night...

s, nacreous clouds, or astronomical objects such as meteors or bright planets with a small percentage even being hoaxes. After excluding incorrect reports, however, it is acknowledged that between 5% and 20% of reported sightings remain unexplained, and as such can be classified as unidentified in the strictest sense. Many reports have been made by trained observers such as pilots, police, and the military; some involve radar traces, so not all reports are visual. Proponents of the extraterrestrial hypothesis
Extraterrestrial hypothesis
The extraterrestrial hypothesis is the hypothesis that some unidentified flying objects are best explained as being extraterrestrial life or non-human aliens from other planets occupying physical spacecraft visiting Earth.-Etymology:...

 believe that these unidentified reports are of alien spacecraft, though various other hypotheses have been proposed.

While UFOs have been the subject of extensive investigation by various governments, and some scientists support the extraterrestrial hypothesis, few scientific papers about UFOs have been published in peer-reviewed journals. There has been some debate in the scientific community
Scientific community
The scientific community consists of the total body of scientists, its relationships and interactions. It is normally divided into "sub-communities" each working on a particular field within science. Objectivity is expected to be achieved by the scientific method...

 about whether any scientific investigation into UFO sightings is warranted.

The void left by the lack of institutional scientific study has given rise to independent researchers and groups, most notably MUFON (Mutual UFO Network) and CUFOS (Center for UFO Studies). The term "Ufology" is used to describe the collective efforts of those who study reports and associated evidence of unidentified flying objects. According to MUFON, as of 2011 the number of UFO reports to their worldwide offices has increased by 67% from the previous 3 years, which now average around 500 reported sightings per month.

UFOs have become a relevant theme in modern culture, and the social phenomena have been the subject of academic research in sociology and psychology.

Terminology


The first publicized sightings were usually referred to using the term mystery airships, which were commonly seen and described as such during the latter part of the 19th century and the early 20th.

The term foo fighter
Foo fighter
The term foo fighter was used by Allied aircraft pilots in World War II to describe various UFOs or mysterious aerial phenomena seen in the skies over both the European and Pacific Theater of Operations....

s was used by American fighter pilots during World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

 to refer to UFOs.

The first widely publicized U.S. sighting, reported by private pilot Kenneth Arnold
Kenneth Arnold
Kenneth A. Arnold was an American aviator and businessman. 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 have seen nine unusual objects flying in a chain near Mount Rainier, Washington...

 in June 1947, gave rise to the popular terms "flying saucer
Flying saucer
A flying saucer is a type of unidentified flying object sometimes believed to be of alien origin 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...

" and "flying disc", of which the former is still sometimes used, even though Arnold said the most of the objects he saw were not totally circular and one was crescent-shaped (see Kenneth Arnold UFO sighting for details). In addition, the infamous Roswell UFO Incident
Roswell UFO incident
The Roswell UFO Incident was the recovery of an object that crashed in the general vicinity of Roswell, New Mexico, in June or July 1947, allegedly an extra-terrestrial spacecraft and its alien occupants. Since the late 1970s the incident has been the subject of intense controversy and of...

 occurred at about the same time, which only served to further fuel public interest in the topic.

The term "UFO" was first suggested in 1952 by Cpt. 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...

, who headed 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...

, then the USAF's official investigation of UFOs. Ruppelt felt that "flying saucer" did not reflect the diversity of the sightings. He suggested that UFO should be pronounced as a word – you-foe. However it is now usually pronounced by forming each letter: U.F.O. His term was quickly adopted by the United States Air Force, which also briefly used "UFOB". The Air Force initially defined UFOs as those objects that remain unidentified after scrutiny by expert investigators, though today the term UFO is often used for any unexplained sighting regardless of whether it has been investigated.

Because the term UFO is ambiguous – referring either to any unidentified sighting, or in popular usage to alien spacecraft
Spacecraft
A spacecraft or spaceship is a craft or machine designed for spaceflight. Spacecraft are used for a variety of purposes, including communications, earth observation, meteorology, navigation, planetary exploration and transportation of humans and cargo....

 – and the public and media ridicule sometimes associated with the topic, some investigators now prefer to use other terms such as unidentified aerial phenomenon (or UAP).

The equivalent acronym for UFO in Spanish, Portuguese, French, and Italian is OVNI (Objeto Volador No Identificado, Objeto Voador Não Identificado, Objet volant non identifié or Oggetto Volante Non Identificato), a term that is pronounced as one word (ov-nee).

Early history


Unexplained aerial observations have been reported throughout history. Some were undoubtedly astronomical in nature: comet
Comet
A comet is an icy small Solar System body that, when close enough to the Sun, displays a visible coma and sometimes also a tail. These phenomena are both due to the effects of solar radiation and the solar wind upon the nucleus of the comet...

s, bright meteor
METEOR
METEOR is a metric 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 that can be seen with the naked eye, planetary conjunctions, or atmospheric optical phenomena
Optical phenomenon
An optical phenomenon is any observable event that results from the interaction of light and matter. See also list of optical topics and optics. A mirage is an example of an optical phenomenon....

 such as parhelia and lenticular cloud
Lenticular cloud
Lenticular clouds are stationary lens-shaped clouds that form at high altitudes, normally aligned perpendicular 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. Such sightings throughout history were often treated as supernatural
Supernatural
The supernatural or is that which is not subject to the laws of nature, or more figuratively, that which is said to exist above and beyond nature...

 portents, angel
Angel
Angels are mythical beings often depicted as messengers of God in the Hebrew and Christian Bibles along with the Quran. The English word angel is derived from the Greek ἄγγελος, a translation of in the Hebrew Bible ; a similar term, ملائكة , is used in the Qur'an...

s, or other religious omen
Omen
An omen is a phenomenon that is believed to foretell the future, often signifying the advent of change...

s. Some current-day UFO researchers have noticed similarities between some religious symbols in medieval paintings and UFO reports though the canonical and symbolic character of such images is documented by art historians placing more conventional religious interpretations on such images.
  • Shen Kuo
    Shen Kuo
    Shen Kuo or Shen Gua , style name Cunzhong and pseudonym Mengqi Weng , was a polymathic Chinese scientist and statesman of the Song Dynasty...

     (1031–1095), a Song Chinese
    Song Dynasty
    The Song Dynasty was a ruling dynasty in China between 960 and 1279; it succeeded the Five Dynasties and Ten Kingdoms Period, and was followed by the Yuan Dynasty. It was the first government in world history to issue banknotes or paper money, and the first Chinese government to establish a...

     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 in the People's Republic of China. Located in eastern China across the basins of the Yangtze River and the Huai 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...

     and Jiangsu
    Jiangsu
    ' is a province 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. The abbreviation for this province is "苏" , the second character of its name...

     (especially in the city of Yangzhou
    Yangzhou
    Yangzhou is a prefecture-level city in central Jiangsu Province, 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 to the east, and Zhenjiang across...

    ), 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 traditional Chinese unit 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.
  • On January 25, 1878, The Denison
    Denison, Texas
    Denison is a city in Grayson County, Texas, United States. The population was 22,773 at the 2000 census; it is estimated to have grown to 24,127 in 2009. Denison is one of two principal cities in the Sherman-Denison Metropolitan Statistical Area.-History:...

     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 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 steamer 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. Comdr. R. R...

    300 miles west of San Francisco, reported by Lt. Frank Schofield
    Frank Herman Schofield
    Frank Herman Schofield 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. As a practical term it refers to the military...

     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. This fleet comprised the main body of ships in the Navy,...

    . 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 NARCAP. On January 31, 1916, a UK pilot near Rochford
    Rochford
    Rochford is a small town in the Rochford district 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
    Wichita, Kansas
    Wichita is the largest city in the U.S. state of Kansas.As of the 2010 census, the city population was 382,368. Located in south-central Kansas on the Arkansas River, Wichita is the county seat of Sedgwick County and the principal city of the Wichita metropolitan area...

    , Kansas and Colorado Springs
    Colorado Springs, Colorado
    Colorado Springs is a Home Rule Municipality that is the county seat and most populous city of El Paso County, Colorado, United States. Colorado Springs is located in South-Central Colorado, in the southern portion of the state. It is situated on Fountain Creek and is located south of the Colorado...

    , Colorado. In late September 1926, an airmail pilot over Nevada
    Nevada
    Nevada is a state in the western, mountain west, and southwestern regions of the United States. With an area of and a population of about 2.7 million, it is the 7th-largest and 35th-most populous state. Over two-thirds of Nevada's people live in the Las Vegas metropolitan area, which contains its...

     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 are one of the longest mountain chains in Asia, extending more than 3,000 km. In the broadest sense, it forms the northern edge of the Tibetan Plateau south of the Tarim Basin and the Gansu Corridor and continues east south of the Wei River to end at the North China Plain.The...

     of Tibet
    Tibet
    Tibet is a plateau region in Asia, north-east of the Himalayas. It is the traditional homeland of the Tibetan people as well as some other ethnic groups such as Monpas, Qiang, and Lhobas, and is now also inhabited by considerable numbers of Han and Hui people...

    's Kokonor
    Qinghai
    Qinghai ; Oirat Mongolian: ; ; Salar:) is a province of the People's Republic of China, named after Qinghai Lake...

     region, Nicholas Roerich
    Nicholas Roerich
    Nicholas Roerich, also known as Nikolai Konstantinovich Rerikh , was a Russian mystic, painter, philosopher, scientist, writer, traveler, and public figure. A prolific artist, he created thousands of paintings and about 30 literary works...

     reported that members of his expedition saw "something big and shiny reflecting the sun, like a huge oval moving at great speed. Crossing our camp the thing changed in its direction from south to southwest. And we saw how it disappeared in the intense blue sky. We even had time to take our field glasses and saw quite distinctly an oval form with shiny surface, one side of which was brilliant from the sun.” Another description by Roerich was, "...A shiny body flying from north to south. Field glasses are at hand. It is a huge body. One side glows in the sun. It is oval in shape. Then it somehow turns in another direction and disappears in the southwest."
  • In the Pacific and European theatres during World War II
    World War II
    World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

    , "Foo-fighters
    Foo fighter
    The term foo fighter was used by Allied aircraft pilots in World War II to describe various UFOs or mysterious aerial phenomena seen in the skies over both the European 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. Some proposed Allied explanations at the time included St. Elmo's Fire
    St. Elmo's fire
    St. Elmo's fire is a weather phenomenon in which luminous plasma is created by a coronal discharge from a grounded object in an electric field in the atmosphere St. Elmo's fire is named after St. Erasmus of Formiae St. Elmo's fire (also St. Elmo's light) is a weather phenomenon in which luminous...

    , the planet Venus, hallucinations from oxygen deprivation, or German secret weapons.
  • On February 25, 1942, U.S. Army observers reported unidentified aircraft both visually and on radar over the Los Angeles, California region. Antiaircraft artillery was fired at what was presumed to be Japanese planes. No readily apparent explanation was offered, though some officials dismissed the reports of aircraft as being triggered by anxieties over expected Japanese air attacks on California. However, Army Chief of Staff Gen. George C. Marshall and Secretary of War Henry Stimson insisted real aircraft were involved. The incident later became known as the Battle of Los Angeles
    Battle of Los Ángeles
    The Battle of Los Ángeles 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, collected primarily by the Swedish military, of unidentified aerial objects 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 Danish Spøgelsesraketter were mysterious rocket- or missile-shaped unidentified flying objects sighted in 1946, mostly in Sweden and nearby countries....

    ", because it was thought that these mysterious objects were possibly Russian tests of captured German V1
    V-1 flying bomb
    The V-1 flying bomb, also known as the Buzz Bomb or Doodlebug, was an early pulse-jet-powered predecessor of the cruise missile....

     or V2
    V-2 rocket
    The V-2 rocket , technical name Aggregat-4 , was a ballistic missile that was developed at the beginning of the Second World War in Germany, specifically targeted at London and later Antwerp. The liquid-propellant rocket was the world's first long-range combat-ballistic missile and first known...

     rocket
    Rocket
    A rocket is a missile, spacecraft, aircraft or other vehicle which obtains thrust from a rocket engine. In all rockets, the exhaust is formed entirely from propellants carried within the rocket before use. Rocket engines work by action and reaction...

    s. Although most were thought to be natural phenomena like meteors, over 200 were tracked on radar and deemed to be "real physical objects" by the Swedish military. In a 1948 top secret
    Top Secret
    Top Secret generally refers to the highest acknowledged level of classified information.Top Secret may also refer to:- Film and television :* Top Secret , a British comedy directed by Mario Zampi...

     document, the Swedish military told the USAF Europe in 1948 that some of their investigators believed them to be extraterrestrial in origin.

The Kenneth Arnold sightings




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 aviator and businessman. 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 have seen nine unusual objects flying in a chain near Mount Rainier, Washington...

 on June 24, 1947 while flying his private plane near Mount Rainier
Mount Rainier
Mount Rainier is a massive stratovolcano located southeast of Seattle in the state of Washington, United States. It is the most topographically prominent mountain in the contiguous United States and the Cascade Volcanic Arc, with a summit elevation of . Mt. Rainier is considered one of the most...

, Washington. He reported seeing nine brilliantly bright objects flying across the face of Rainier.

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 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., is the world's largest airline with 86,852 employees United Air Lines, Inc., is the world's largest airline with 86,852 employees United Air Lines, Inc., is the world's largest airline with 86,852 employees (which includes the entire holding company United Continental...

 crew sighting of nine more disc-like objects over Idaho
Idaho
Idaho is a state in the Rocky Mountain area of the United States. The state's largest city and capital is Boise. Residents are called "Idahoans". Idaho was admitted to the Union on July 3, 1890, as the 43rd state....

 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". Speculation as to what the flying saucers were was rampant in the newspapers. Theories ranged from hallucinations, mass hysteria, optical illusions, hoaxes, reflections off airplanes, unusual atmospheric conditions, and weather balloons to byproducts of atomic testing or U.S./Russian secret weapons, to even more esoteric interdimensional or interplanetary visitors. 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 was the recovery of an object that crashed in the general vicinity of Roswell, New Mexico, in June or July 1947, allegedly an extra-terrestrial spacecraft and its alien occupants. Since the late 1970s the incident has been the subject of intense controversy and of...

, in which they explained debris found on the ground by a rancher as being that of a weather balloon.

Over several years in the 1960s, Bloecher (aided by physicist James E. McDonald
James E. McDonald
James Edward McDonald was an American physicist. He is best known for his research regarding UFOs. McDonald was senior physicist at the Institute for Atmospheric Physics and professor in the Department of Meteorology, University of Arizona, Tucson.McDonald campaigned vigorously in support of...

) discovered 853 flying disc sightings that year from 140 newspapers from Canada, Washington D.C, and every U.S. state except Montana.

Investigations


UFOs have been subject to investigations over the years that vary widely in scope and scientific rigor. Governments or independent academics in the United States, Canada, the United Kingdom, Japan, Peru, France, Belgium, Sweden, Brazil, Chile, Uruguay, Mexico, Spain, and the Soviet Union are known to have investigated UFO reports at various times. These official reports refer to the UFO of military term, and not, to the supposed alien crafts. It dose not mean that the above-mentioned governments recognized supposed human contact with alien civilization.

Among the best known government studies are the ghost rockets
Ghost rockets
Ghost Rockets Danish Spøgelsesraketter were mysterious rocket- or missile-shaped unidentified flying objects sighted in 1946, mostly in Sweden and nearby countries....

 investigation by the Swedish military (1946–1947), 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 and active for most of 1948....

 and Project Grudge
Project Grudge
Project Grudge was a short-lived project by the U.S. Air Force to investigate unidentified flying objects . Grudge succeeded Project Sign in February, 1949, and was then followed by Project Blue Book. The project formally ended in December 1949, but actually continued on in a very minimal capacity...

, conducted by the United States Air Force
United States Air Force
The United States Air Force is the aerial warfare service branch of the United States Armed Forces and one of the American uniformed services. Initially part of the United States Army, the USAF was formed as a separate branch of the military on September 18, 1947 under the National Security Act of...

 from 1947 until 1969, the secret U.S. Army/Air Force Project Twinkle investigation into green fireballs
Green Fireballs
Green fireballs are a type of unidentified flying object which have been sighted in the sky since the late 1940s . Early sightings primarily occurred in the southwestern United States, particularly in New Mexico...

 (1948–1951), the secret USAF Project Blue Book Special Report #14 by the Battelle Memorial Institute
Battelle Memorial Institute
Battelle Memorial Institute is a private nonprofit applied science and technology development company headquartered in Columbus, Ohio. Battelle is a charitable trust organized as a nonprofit corporation under the laws of the State of Ohio and is exempt from taxation under Section 501 of the...

, and Brazilian Air Force Operation Saucer (1977). France has had an ongoing investigation (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....

) within its space agency CNES
CNES
The is the French government space agency . Established under President Charles de Gaulle in 1961, its headquarters are located in central Paris and it is under the supervision of the French Ministries of Defence and Research...

 since 1977, as has Uruguay since 1989.

Project Sign


Project Sign in 1948 wrote a highly classified opinion (see 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. Sneider - which explained their reasons for concluding that the extraterrestrial hypothesis was the best...

) that the best UFO reports probably had an extraterrestrial explanation, as did the private but high-level French COMETA
COMETA
COMETA was a high-level French 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...

 study of 1999. A top secret Swedish military opinion given to the USAF in 1948 stated that some of their analysts believed the 1946 ghost rockets
Ghost rockets
Ghost Rockets Danish Spøgelsesraketter were mysterious rocket- or missile-shaped unidentified flying objects sighted in 1946, mostly in Sweden and nearby countries....

 and later flying saucers had extraterrestrial origins. (see Ghost rockets
Ghost rockets
Ghost Rockets Danish Spøgelsesraketter were mysterious rocket- or missile-shaped unidentified flying objects sighted in 1946, mostly in Sweden and nearby countries....

 for document). In 1954, German rocket scientist Hermann Oberth
Hermann Oberth
Hermann Julius Oberth was an Austro-Hungarian-born German physicist and engineer. He is considered one of the founding fathers of rocketry and astronautics.- Early life :...

 revealed an internal West German government investigation, which he headed, that arrived at an extraterrestrial conclusion, but this study was never made public.

Project Magnet


Classified, internal reports by the Canadian Project Magnet
Project Magnet
Project Magnet was an unidentified flying object study programme established by the Canadian Department of Transport on December 2, 1950, under the direction of Wilbert B. Smith, senior radio engineer for the DOT's Broadcast and Measurements Section...

 in 1952 and 1953 also assigned high probability to extraterrestrial origins. Publicly, however, Project Magnet, nor later Canadian defense studies, ever stated such a conclusion.

Project Grudge


Project Sign was dismantled and became Project Grudge
Project Grudge
Project Grudge was a short-lived project by the U.S. Air Force to investigate unidentified flying objects . Grudge succeeded Project Sign in February, 1949, and was then followed by Project Blue Book. The project formally ended in December 1949, but actually continued on in a very minimal capacity...

 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, using the Condon Commission's negative conclusion as a rationale, 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 that 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." In addition, in the late 1960s, there was a chapter on UFOs at the U.S. Air Force Academy in their Space Sciences course, giving serious consideration to possible extraterrestrial origins. When word of the curriculum became public, the Air Force in 1970 put out a statement the book was outdated and that cadets were now being informed of Condon's negative conclusion instead.

USAF Regulation 200-2


The initially classified USAF Regulation 200-2, first issued in 1953 after the Robertson Panel, which first defined UFOs and how information was to be collected, stated explicitly that the two reasons for studying the unexplained cases were for national security reasons and for possible technical aspects involved, implying physical reality and concern about national defense, but without opinion as to origins. (For example, such information would also be considered important if UFOs had a foreign or domestic origin.) The first two known classified USAF studies in 1947 also concluded real physical aircraft were involved, but gave no opinion as to origins. (See American investigations immediately below) These early studies led to the creation of 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 and active for most of 1948....

at the end of 1947, the first semi-public USAF study.