Unidentified flying object: Difference between revisions

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Sightings increased greatly following the [[Second World War]], and in 1947 the [[U.S. government]] began studying them, often in [[classified information|classified]] projects. There is, however, a distinct difference between unidentified aerial objects and these theoretical constructs.  All mainstream investigators and scientists readily concede that the explanation of some aerial sightings remains unidentified even after the most intense examination.  Most, or perhaps close to all of them, however, dismiss the notion that there is any concrete evidence that Earth is being, or has been, visited by creatures from other worlds.
Sightings increased greatly following the [[Second World War]], and in 1947 the [[U.S. government]] began studying them, often in [[classified information|classified]] projects. There is, however, a distinct difference between unidentified aerial objects and these theoretical constructs.  All mainstream investigators and scientists readily concede that the explanation of some aerial sightings remains unidentified even after the most intense examination.  Most, or perhaps close to all of them, however, dismiss the notion that there is any concrete evidence that Earth is being, or has been, visited by creatures from other worlds.


There is a movement, loosely called "ufology", that distrusts government investigations and publishes its own observations. Much of the reporting of these organizations is anecdotal and hard to put into a scientific framework, but some of the leadership of UFO research centers, such as [[Mark Rodeghier]] of the [[Center for UFO Studies]] (CUFOS) and [[Jacques Vallée]], do participate in much more technical discussions such as the of a 1997 symposium on physical evidence from UFOsP.A. Sturrock, who directed the study, held with the encouragement of Laurance Rockefeller, "agreed that the problem is in a very unsatisfactory state of ignorance and confusion. I expressed the opinion that this
There is a movement, loosely called "ufology", that distrusts government investigations and publishes its own observations. Much of the reporting of these organizations is anecdotal and hard to put into a scientific framework, but some of the leadership of UFO research centers, such as [[Mark Rodeghier]] of the [[Center for UFO Studies]] (CUFOS) and [[Jacques Vallée]], do participate in much more technical discussions, such as the 1997 symposium on physical evidence from UFOs. P.A. Sturrock, who directed the study, held with the encouragement of Laurance Rockefeller, "agreed that the problem is in a very unsatisfactory state of ignorance and confusion. I expressed the opinion that this
problem will be resolved only by extensive and open professional scientific
problem will be resolved only by extensive and open professional scientific
investigation, and that an essential prerequisite of such research is that more
investigation, and that an essential prerequisite of such research is that more

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See also: Extraterrestrial intelligence

Unidentified flying objects, commonly called UFOs or U.F.O.s, are any aerial phenomena that cannot be initially identified. In many cases, even most, they are subsequently identified as being aircraft, birds, heavenly bodies, or other everyday objects; they can also be errors produced internally to a radar, electro-optical, or other sensor. Even so, a number of credible observations exist that, although something was clearly present, cannot be explained. Throughout the world, at least since 1947, they have been conflated with so-called "flying saucers" or other vehicles that might be directed by extraterrestrial intelligences either from other planets in this Solar system or from other stars.

Sightings increased greatly following the Second World War, and in 1947 the U.S. government began studying them, often in classified projects. There is, however, a distinct difference between unidentified aerial objects and these theoretical constructs. All mainstream investigators and scientists readily concede that the explanation of some aerial sightings remains unidentified even after the most intense examination. Most, or perhaps close to all of them, however, dismiss the notion that there is any concrete evidence that Earth is being, or has been, visited by creatures from other worlds.

There is a movement, loosely called "ufology", that distrusts government investigations and publishes its own observations. Much of the reporting of these organizations is anecdotal and hard to put into a scientific framework, but some of the leadership of UFO research centers, such as Mark Rodeghier of the Center for UFO Studies (CUFOS) and Jacques Vallée, do participate in much more technical discussions, such as the 1997 symposium on physical evidence from UFOs. P.A. Sturrock, who directed the study, held with the encouragement of Laurance Rockefeller, "agreed that the problem is in a very unsatisfactory state of ignorance and confusion. I expressed the opinion that this problem will be resolved only by extensive and open professional scientific investigation, and that an essential prerequisite of such research is that more scientists acquire an interest in this topic." The symposium ("Physical evidence") was supported by the LSE Fund and conducted by the Society for Scientific Exploration.[1]

Criteria for reliable observation

"Seven experienced UFO investigators were asked to review specific categories of evidence. Dr. Richard F. Haines of Los Altos, California, undertook to review photographic evidence and also reviewed aircraft equipment anomalies; Dr. Illobrand von Ludwiger of Feldkirchen-Westerham, Germany, discussed radar evidence; Dr. Mark Rodeghier of the Center for UFO Studies in Chicago discussed automobile engine anomalies; Mr. John F. Schuessler of Houston discussed injuries to witnesses; Dr. Erling Strand from Ostfeld, Norway, presented evidence involving video records and spectroscopic data; Dr. Michael D. Swords, Professor in the General Studies Science Department at Eastern Michigan University discussed inertial anomalies; Dr. Jacques F. Vallée of San Francisco presented energy estimates and also discussed material evidence; and M. Jean-Jacques Velasco of CNES, Toulouse, France, presented evidence concerning radar events, ground traces, and injuries to vegetation."

Visual light spectrum

The JSE report said "The panel expressed the opinion that detailed analysis of photographic evidence was unlikely by itself to yield evidence sufficient to convince a neutral scientist of the reality of a new strange phenomenon unless a number of additional detailed conditions are met.... They also expressed concern that, now that modern digital techniques are easily available in photo laboratories, it may never be possible to rule out possible hoaxes without convincing, corroborative eye-witness accounts."[2]

Considerable attention was given to luminosity of objects, which were often described as very bright lights. This is especially important in the reports of the French astronomer and UFO researcher, Jacques Vallée. He described six visual sightings, with estimates of power into the megawatt range. "Vallée cautioned the panel that the estimates of luminosity presented at the workshop are raw approximations derived from a comparison of the estimated intensity in the visible band with the intensity of known sources, such as the full moon and automobile headlights, and from assumptions concerning the distance and perhaps size of the source. The panel noted that the human eye is a very poor device for measuring absolute luminosities: the state of dark adaptation of the eye affects the amount of light reaching the retina, and different parts of the retina respond differently to light. Furthermore, the above luminosity estimates were apparently based on the assumption of isotropic emission. This may be a reasonable assumption for a natural phenomenon, but could be inappropriate if a case involves a technological device. For instance, aircraft landing lights are highly anisotropic. A 1 kW source that is beamed with a half-angle of 3.6 degrees has the same intensity as a 1 Mw isotropic emitter. Furthermore, the distance estimates may be quite dubious. Hence the power estimates derived for the above cases must be considered quite uncertain."[3]

Radar

See also: Radar MASINT

Radar technology has improved constantly since 1947. Even the 1997 symposium warned against accepting radar reports without other confirmation. Military radar is far more informative about object analysis than is civilian air traffic control.

With UFOs, however, the challenge is having a radar within range of a sighting, and also getting full access to military records. In the 1990s, however, the Swiss and French militaries provided UFO researchers with substantial access. Two incidents did provide correlated visual and radar information.

Spectrometry

See also: Electro-optical MASINT

Electromagnetic interference

See also: Geophysical MASINT

Gravitational or inertial

Ground traces

Injuries to vegetation

Effects on witnesses

Analysis of debris

See also: Materials MASINT
See also: Materials MASINT

History

Since the advent of aviation, there have been both instrumental and visual detections of things that could not be explained at the time. The term "gremlin" was used to describe, among other electronic phenomena, unexplained readings from World War II radar systems. There are also many misidentifications, such as the interpretation of the radar detection of the incoming Japanese force at the Battle of Pearl Harbor as incoming friendly B-17 bombers.

When the AN/FPS-50 early warning radar, part of the Ballistic Missile Early Warning System (BMEWS), went into service in 1960, it soon reported a massive Soviet missile attack on the U.S., which proved to be due to unexpected reflections of the radar beam from the Moon.

The Kenneth Arnold sighting

UFOs became popularly known as flying saucers after a story in the East Oregonian newspaper, on June 26, 1947, reported salesman Kenneth Arnold's sighting of extremely fast-moving, "saucer-like objects" while flying a private plane.[4] A subsequent follow-up newspaper story coined the term "flying saucer" to describe the objects that Arnold reported sighting. According to the Mutual UFO Network, there is conflict about both the UFO and flying saucer terms:

U.S. Air Force Capt. Edward J. Ruppelt says unequivocally that "UFO is the official term that I created to replace the words flying saucers"[5]. Presumably this would have been sometime between 1951, when Ruppelt took over Project Grudge (later renamed Blue Book), and September of 1953, when he left the agency and the Air Force. Elsewhere in the same book, however, Ruppelt says of Project Grudge's final 600-page report, released in December of 1949, that it was "officially titled Unidentified Flying Objects - Project Grudge, Technical Report No. 102-AC-49/15-100. But it was widely referred to as the Grudge Report."[6] This would mean that some long forgotten anonymous Air Force staffer coined the phrase at least two years before Ruppelt did. But perhaps Ruppelt was only claiming credit for coinage of the acronym UFO.[7]

Arnold self-published reports of the incident, which have been called hysteria by an affiliate of the Skeptical Inquirer.[8]

Roswell incident

In July 1947, there were reports of a flying saucer crash at Roswell, New Mexico. Some reports suggest it was a classified, balloon-borne sensor, developed by the U.S., and intended to gather intelligence on Soviet nuclear weapons. Others, however, believe there was evidence of extraterrestrial origin, and possible government coverups.[9]

On September 8, 1994, the Secretary of the Air Force, Sheila Widnall, announced that the United States Air Force had completed its study to locate records relating to the Roswell incident. "Pro-UFO researchers claim that an extraterrestrial spacecraft and its alien occupants were recovered near Roswell in July of 1947, and that this fact was kept from the public."

"At the request of Congressman Steven H. Schiff (R-NM), the General Accounting Office (GAO) initiated an audit in February of 1994, to locate all records relating to the "Roswell Incident" and to determine if such records were properly handled. The GAO audit was completed and the results published by the Headquarters, U.S. Air Force in 1995. The publication is entitled "The Roswell Report: Fact vs. Fiction in the New Mexico Desert." This publication may be obtained from most U.S. Government Depository Library. The call number is ISBN 0-16- 048023-X....Prior to the interviews, Secretary Widnall released those persons from any previous security obligations that may have restricted their statements.

"The Air Force research did not locate or develop any information that the "Roswell Incident" was a UFO event nor was there any indication of a "cover-up" by the Government. Information obtained through exhaustive records searches and interviews indicated that the materials recovered near Roswell was consistent with a balloon devise of the type used in a then classified project. No records indicated or even hinted that the recovery of "alien" bodies or extraterrestrial materials."[10]

Reports also indicate that a govenment task force, called Majestic-12, may have been formed to manage the alien information. The Majestic code, however, has also been associated with classified continuity of government, or "shadow government", programs that were confirmed in the Eisenhower Administration and may have existed in the Truman Administration.

Government investigation

After the Second World War, the U.S. and other government investigated UFO reports.

Project BLUE BOOK

The major U.S. Air Force activity was called Project Blue Book, and was in existence between 1947 and 1967. It was terminated after a study called the Condon Report, coordinated by the University of Colorado, entitled, "Scientific Study of Unidentified Flying Objects;" a review of the University of Colorado's report by the National Academy of Sciences; and past UFO studies and Air Force experience investigating UFO reports during the 40s, '50s, and '60s, led the Secretary of the Air Force to determine there was no national security value to continuing investigations.

"From 1947 to 1969, a total of 12,618 sightings were reported to Project BLUE BOOK. Of these 701 remain "Unidentified." The project was headquartered at Wright-Patterson Air Force Base, whose personnel no longer receive, document or investigate UFO reports.[10] Note below that the CIA studied until 1990.

Records of the project are in the U.S. National Archives.[10]The National Archives searched for Majestic-12, and one document, a "Memorandum for General Twining, from Robert Cutler, Special Assistant to the President, Subject: "NCS/MJ-12 Special Studies Project" dated July 14, 1954. The memorandum, one page, refers to a briefing to take place on July 16. The memorandum does not identify MJ-12 or the purpose of the briefing." Nathan Twining was the Chairman of the Joint Chiefs of Staff. There has been some speculation, by the Federation of American Scientists and others, that this may have some relationship to what has also been called the "Eisenhower 10" continuity of government project.[11]

The National Archives, however, found several inconsistencies regarding the NCS/MJ-12 Project document. Cutler was out of the country on the date marked on the document. It does not bear a registration number appropriate to the record series, it is not on a letterhead and is on a type of carbon paper not used for any of Cutler's other documents, and it bears a classification marking not in use until the Nixon Administration.

Another Air Force report was issued in 1997. The J. Allen Hynek Center for UFO Studies (CUFOS) (see below) disputes the Air Force report on the incident.[12]

Condon Report

Following publication of the BLUE BOOK report, in 1967, the Air Force issued a contract, to the University of Colorado, for the study of unidentified flying objects. Brigadier General Edward B. Gillers, USAF, was the contract monitor, Dr. Thomas Rachford was the senior Air Force Scientist on the project, and the principal investigator from the University was Dr. E.U. Condon, director of the National Bureau of Standards from 1946 to 1950. This report was subsequently reviewed, with approval, by the National Academy of Sciences.

The project was able to get some support from the Central Intelligence Agency.

Central Intelligence Agency

Central Intelligence Agency (CIA) documents indicate that the agency monitoried the UFO situation starting in 1952.[13]

Early CIA interest

Although it had monitored UFO reports for at least three years, CIA reacted to the new rash of sightings, in 1952, by forming a special study group within the Office of Scientific Intelligence (OSI) and the Office of Current Intelligence (OCI) to review the situation. Edward Tauss, acting chief of OSI's Weapons and Equipment Division, reported for the group that most UFO sightings could be easily explained. Nevertheless, he recommended that the Agency continue monitoring the problem, in coordination with the Air Force Technical Intelligence Center (ATIC). He also urged that CIA conceal its interest from the media and the public, "in view of their probable alarmist tendencies" to accept such interest as confirming the existence of UFOs.

Upon receiving the report, Deputy Director for Intelligence (DDI) Robert Amory, Jr. assigned responsibility for the UFO investigations to OSI's Physics and Electronics Division, with A. Ray Gordon as the officer in charge. Each branch in the division was to contribute to the investigation, and Gordon was to coordinate closely with ATIC. Amory, who asked the group to focus on the national security implications of UFOs, was relaying DCI Walter Bedell Smith's concerns. Smith wanted to know whether or not the Air Force investigation of flying saucers was sufficiently objective and how much more money and manpower would be necessary to determine the cause of the small percentage of unexplained flying saucers. Smith believed "there was only one chance in 10,000 that the phenomenon posed a threat to the security of the country, but even that chance could not be taken." According to Smith, it was CIA's responsibility by statute to coordinate the intelligence effort required to solve the problem. Smith also wanted to know what use could be made of the UFO phenomenon in connection with US psychological warfare efforts.

Air Force contract team meeting with NPIC's Art Lindahl

In 1967, the Air Force issued a contract, to the University of Colorado, for the study of unidentified flying objects. Brigadier General Edward B. Gillers, USAF, was the contract monitor, Dr. Thomas Rachford was the senior Air Force Scientist on the project, and the principal investigator from the University was Dr. E.U. Condon, eminent physicist and director of the National Bureau of Standards from 1946 to 1950.

"On 20 February 1967 at 0915 Dr. Condon and four members of his investigative team visited NPIC. With Dr. Condon were Dr. Richard Love, University of Colorado, Dr. David Saunders, University of Colorado, Dr. William Price, Executive Director of APRST, and Dr. Rachford, USAF. The purpose of this visit was to familiarize Dr. Condon and members of his team with selected photogrammetric and photographic analysis capabilities of the National Photographic Interpretation Center (NPIC). Art Lundahl, the dean of photographic interpretation met with the investigators.[14]

The meeting was allowed to discuss classified material through the SECRET level. NPIC established ground rules:

"Any work performed by NPIC to assist Dr. Condon in his investigation will not be identified as work accomplished by CIA. Dr. Condon was advised by Mr. Lundahl to make no reference to CIA in regard to this work effort. Dr. Condon stated that if he felt it necessary to obtain an official CIA comment he would make a separate distinct entry into CIA not related to contacts he has with NPIC.
"NPIC will not prepare any written comments, will not analyze information with the intent of drawing a conclusion, nor prepare written reports. NPIC personnel will be available to assist Dr. Condon by performing work of photogrammetric nature, such as attempting to measure objects imaged on photographs that may be part of Dr. Condon's analysis. Work performed by NPIC will be strictly of a technical nature using services and equipment generally not available elsewhere."

In summary, "At about 1235 the group adjourned to lunch and following lunch they left NPIC for a meeting with Brig.Gen Gillers at the Pentagon."

"Most all the discussion during the morning was of an unclassified nature dealing with primary basic fundamentals of photogrammetry, photographic analysis and problems related to the acquiring of enough information to conduct meaningful analyses."

Condon and the same group met again in May 1967 at NPIC to hear an analysis of UFO photographs taken at Zanesville, Ohio. The analysis debunked that sighting. The committee was again impressed with the technical work performed, and Condon remarked that for the first time a scientific analysis of a UFO would stand up to investigation.

National Academy of Sciences review

A panel of the National Academy of Sciences reviewed the Condon Report in 1969. It was chaired by Gerald Clemence of Yale University; the other members were H.R. Crane (University of Michigan), Mark Kac (Rockefeller University), Francis Reichelderfer (former director of the U.S. Weather Service), Wallace Fenn (University of Rochester), William Rubey (University of California at Los Angeles), H. Keffer Hartline (Rockefeller University), C.D. Shane (Santa Cruz, CA), E.R. Hildgard and Oswald Villard (Stanford University) . They observed

We are unanimous in the opinion that this has been a very creditable effort to apply objectively the relevant techniques of science to the solution of the UFO problem. The Report recognizes that there remain UFO sightings that are not easily explained. The Report does not suggest, however, so many reasonable and possible directions in which an explanation may eventually be found, that there seems to be no reason to attribute them to an extraterrestrial source without evidence that is much more convincing. The Report also shows how difficult it is to apply scientific methods to the occasional transient sightings with any chance of success. While further study of particular aspects of the topic (e.g., atmospheric phenomena) may be useful, a study of UFOs in general is not a promising way to expand scientific understanding of the phenomena. On the basis of present knowledge the least likely explanation of UFOs is the hypothesis of extraterrrestrial visitations by intelligent beings.[15]

UFO Classification

Several groups interested in UFOs, however, have made efforts to catalog information on reports of them. In the United States, there are two major and well known UFO groups in the United States. They are the J. Allen Hynek Center for UFO Studies (CUFOS) founded by J. Allen Hynek, who was the chairman of astronomy at Northwestern University; and the Mutual UFO Network (MUFON) lead by Allen Utke, Associate Professor of Chemistry at Wisconsin State University. There is also work by a French-born researcher, Jacques Vallée.

Hynek originally doubted that the reports had any substance, but later changed his mind about UFOs during his research with Project BLUE BOOK.[16]. CUFOS collects UFO reports, maintains a UFO research library, and offers two publications concerning the UFO phenomena.

There are two major systems for classifying the reports, first based on shape and other visually observed characteristics, movement, and interaction with the environment or possible entities.

Certain of these classifications, however, specifically assume not only an object that could not be explained, but also indications of a nonhuman intelligence, either extraterrestrial or terrestrial but paranormal. While mainstream science does work in a Search for Extraterrestrial Intelligence, its focus has been on intelligently generated radio signals, not physical visitation.

Hynek's Classification

J. Allen Hynek was the chairman of astronomy at Northwestern University and offered technical assistance for the United States Air Force Project BLUE BOOK. He was a UFO skeptic but went onto to believe in the UFO phenomena. He later founded the Center for UFO Studies in Chicago, Illinois.

  • Observational aspects
    • Nocturnal Disks: Objects seen in the night sky. This is the most commonly reported UFO sighting.
    • Daylight Disks: UFOs that could be seen flying high in the sky or close to the ground. Oval or round disks are commonly seen with this type of UFO sighting.
    • Radar Visual: UFOs that are seen on radar screens while also being visually confirmed by eyewitnesses on the ground.
    • (not listed in classification, but radar-only would seem needed)
  • Behavioral aspects
    • Close Encounter of the First Kind: UFOs that are seen within 200 yards of the witness. There is no interaction between the witness and the UFO.
    • Close Encounter of the Second Kind: Electrical equipment such as a car ignition may operate strangely. Other electrical equipment may malfunction while the UFO is present. Other forms of interaction may include physical effects to plants, animals or human beings. There could be traces of burned grass for example in a Close Encounter of the Second Kind.
    • Close Encounter of the Third Kind: Seeing humanoid like creatures associated with the UFO. There is usually no interaction between the human witness and the humanoid. In some reports there have been interactions reported between the UFO witness and the humanoids.[17]
    • Close Encounters of the Fourth Kind: Interaction between the UFO witness and abduction by humanoid entities.[18]

Jacques Vallée's UFO Classification

Jacques F. Vallée is a French-born astronomer active in studies of UFOs.

  • AN1: Viewing anomalous lights or explosions in the sky that do not affect the witness or the environment.
  • AN2: Reports that show lasting effects such as flattened grass, poltergeist activity or anomalous photographs.
  • AN3: Cases that include entities. This could include ghosts, yetis (Abominable Snowman), elves, spirits and cryptozoology.
  • AN4: The witness reports interaction with the entities within the reality of the entities themselves. This type of experience could include near-death experiences, religious visions and out-of-body experiences (OBEs).
  • MA1: A UFO that drops, maneuvers, loops.
  • MA2: A UFO that includes a physical interaction with the environment while performing drops, maneuvers or loops. An example of this would be seeing a UFO near a power plant.
  • MA3: Witnessing entities on board a UFO while performing the above mentioned maneuvers.
  • MA4: The UFO witness observes the listed actions and goes through a transformational experience during the event.
  • MA5: The UFO witness suffers serious or injury as a result of seeing a UFO in the sky.[18]

UFO shapes

UFOs have been reported in varying shapes and colors. According to the National UFO Reporting Center statistics, 12,023 lights were reported, 6,020 triangles were reported, 5,181 circles and 4,784 disks were reported as of July 2010.[19] Reports in the database are transcriptions of witness self-reports and are not cross-indexed, correlated, or evaluated.

Categorizing shapes is considered a challenging problem in both visual perceptual psychology and computer vision.

To recognize a previously seen object, the visual system must overcome the variability in the object's

appearance caused by factors such as illumination and pose. Developments in computer vision suggest that it may be possible to counter the in£uence of these factors, by learning to interpolate between stored views of the target object, taken under representative combinations of viewing conditions. Daily life situations, however, typically require categorization, rather than recognition, of objects. Due to the open-ended character of both natural and arti¢cial categories, categorization cannot rely on interpolation between

stored examples.[20]

Note that the cited study deals with recognition of previously seen objects. The categorization of objects of a type never before encountered is more difficult.

The home page of the National UFO Reporting Center notes

Events across the United States and Canada on the evening of Sunday, July 04, 2010

Over the last 48 hours, NUFORC has received almost 100 similar reports of very peculiar events, which have been witnessed across the U. S. and Canada on July 4th, and perhaps on July 3rd, as well. The sightings are a phenomenon for which we have no ready explanation. Many of the reports from both days have been submitted by seemingly serious-minded individuals, many of whom apparently witnessed the events with multiple other witnesses present.

To date, we have received reports of the phenomenon from the following U. S. states and Canadian provinces: California; Connecticut; Washington, D.C.; Florida; Georgia; Illinois; Indiana; Kentucky; Massachusetts; Manitoba; Michigan; Minnesota; Missouri; North Dakota; Nebraska; New Jersey; New York; Ohio; Oklahoma; Pennsylvania; Tennessee; Texas; Virginia; Vermont; and Washington State.

The reports are similar, in that the witnesses have described seeing strange red, orange, or yellow “fireballs,” which have been seen either to hover in the night sky, or to streak overhead, sometimes individually, and on some occasions in clusters. In some instances, the objects were observed against a clear, cloudless sky, and in other cases, they were observed below solid or broken overcast.[21]

The center did not plot the events by time, by location, or correlate appearance and movement versus time or observer position. It can be noted that on the nights of July 4 in the United States, there routinely is a high incidence of unusual lights in the sky. Indeed, an exceptionally high incidence of lights in the sky was reported on July 4, 2009, by the Mutual UFO Network.[22]

It should be noted that bright lights of normal origin, against a dark sky, can produce visual afterimages of substantial duration. Point sources can appear to have trails of light.[23]

This is not to suggest, however, that there were no unexplainable reports among these. It is, however, extremely difficult to correlate among the witness reports. The U.S. is not covered by precision radar and there may be no other non-visual sensors. Air Traffic Control uses transponder, not radar, tracking.

References

  1. P.A. Sturrock et al. (1998), "Physical Evidence from UFO Reports", Journal of Scientific Exploration 12 (2): 179-229
  2. "Physical Evidence", p. 189
  3. "Physical Evidence", pp0. 190-191
  4. Bill Bequette (26 June 1947), Boise Flyer Maintains He Saw 'Em, Pendleton, Oregon East Oregonian
  5. Report on Unidentified Flying Objects, Doubleday, 1956, p. 6
  6. Unidentified Flying Objects, United States Air Force Project Grudge, Technical Report No. 102-AC-49/15-100.
  7. Frequently Asked Questions, Mutual UFO Network (MUFON)
  8. Robert E. Bartholomew and Erich Goode (May-June 2000), Mass Delusions and Hysterias: Highlights from the Past Millennium, vol. 24.3, Committee for Skeptical Inquiry
  9. The Roswell Incident, New Mexicans for Science and Reason
  10. 10.0 10.1 10.2 Unidentified Flying Objects - Project BLUE BOOK, National Archives and Records Administration Cite error: Invalid <ref> tag; name "NARA-UFO" defined multiple times with different content
  11. President Eisenhower Designated Private Citizens to Take Control of the Government in the Event of a Nuclear Attack on the United States
  12. Mark Rodeghier, The Center For UFO Studies Response To The Air Force’s 1997 Report, The Roswell Report: Case Closed, J. Allen Hynek Center for UFO Studies (CUFOS)
  13. Gerald K. Haines, "CIA's Role in the Study of UFOs, 1947-90: A Die-Hard Issue", Studies in Intelligence, Central Intelligence Agency
  14. Visit of Dr. Condon to NPIC, 20 February 1967. Retrieved on 2007-10-29.
  15. Review of the University of Colorado Report on Unidentified Flying Objects by a Panel of the National Academy of Sciences, National Academy of Sciences, 1969
  16. Center for UFO Studies
  17. J.Allen Hynek Center for UFO Studies
  18. 18.0 18.1 Jacques F. Vallée (April 2007), A System of Classification and Reliability Indicators for the Analysis of the Behavior of Unidentified Aerial Phenomena
  19. Report Index by Shape of Craft, National UFO Report Center
  20. Shimon Edelman and Sharon Duvdevani-Bar (1997), "A model of visual recognition and categorization", Phil.Trans. R. Soc. Lond. B 352: 1191-1202
  21. Events across the United States and Canada on the evening of Sunday, July 04, 2010, National UFO Reporting Center, 6 July 2010
  22. "UFOs spotted over 10 states during July 4th celebrations", Boston Examiner, 5 July 2009
  23. E. Bruce Goldstein (2007), Cognitive psychology: connecting mind, research, and everyday experience, Wadsworth, pp. 143-145