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Unidentified flying object

Unidentified flying object is a physics topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Unidentified flying object rather than just read about it. In short: An unidentified flying object (UFO) is an object or phenomenon seen in the sky but not yet identified or explained. The term was coined when United States Air Force (USAF) investigations into flying saucers found too broad a range of shapes reported to consider them all saucers or discs.

Unidentified flying object — main illustration
Unidentified flying object — illustration

Key takeaways

  • Unidentified flying object belongs to physics; place it in that map before memorising details.
  • Learn the definition first, then one example that makes the definition concrete.
  • Connect Unidentified flying object to a quantity you can measure, compute or draw — that is where exam questions come from.
  • Reproduce the core statement of Unidentified flying object from memory before moving on to harder problems.

Reference excerpt

An unidentified flying object (UFO) is an object or phenomenon seen in the sky but not yet identified or explained. The term was coined when United States Air Force (USAF) investigations into flying saucers found too broad a range of shapes reported to consider them all saucers or discs. UFOs are also known as unidentified aerial phenomena or unidentified anomalous phenomena (UAPs). Upon investigation, most UFOs are identified as known objects, natural phenomena, hoaxes, or mirages, while a small number remain unexplained. While unusual sightings in the sky have been reported since at least the 3rd century BC, UFOs became culturally prominent after World War II, escalating during the Space Age. Studies and investigations into UFO reports conducted by governments (such as Project Blue Book in the United States and Project Condign in the United Kingdom), as well as by organisations and individuals have occurred over the years without confirmation of the fantastical claims of small but vocal groups of ufologists who favour unconventional or pseudoscientific hypotheses, often claiming that UFOs are evidence of extraterrestrial intelligence, technologically advanced cryptids, interdimensional contact, future time travelers, demons or the Dead. After decades of promotion of such ideas by believers and in popular media, the kind of evidence required to solidly support such claims has not been forthcoming. Scientists and skeptic organizations such as the Committee for Skeptical Inquiry have provided prosaic explanations for UFOs, namely that they are caused by natural phenomena, human technology, delusions, and hoaxes. Although certain beliefs surrounding UFOs have inspired parts of new religions, social scientists have identified the ongoing interest and storytelling surrounding UFOs as a modern example of folklore and mythology understandable with psychosocial explanations. The problems of temporarily or permanently non-knowable anomalous phenomenon or perceived objects in flight is part of the philosophical subject epistemology. The U.S. government has two entities dedicated to UFO data collection and analysis: NASA's UAP independent study team and the Department of Defense All-domain Anomaly Resolution Office.

Terminology and prevalence of belief During the late 1940s and through the 1950s, UFOs were often called "flying saucers" or "flying discs" based on reporting of the Kenneth Arnold incident. "Unidentified flying object" (UFO) has been in-use since 1947. The acronym "UFO" was coined by Captain Edward J. Ruppelt for the USAF. He wrote, "Obviously the term 'flying saucer' is misleading when applied to objects of every conceivable shape and performance. For this reason the military prefers the more general, if less colorful, name: unidentified flying objects. UFO". The term UFO became widespread during the 1950s, at first in technical literature, but later in popular use. "Unidentified aerial phenomenon" (UAP) first appeared in the late 1960s. UAP has seen increasing usage in the 21st century due to negative cultural associations with "UFO". UAP is sometimes expanded as "unidentified anomalous phenomenon". While technically a UFO refers to any unidentified flying object, in modern popular culture the term UFO has generally become synonymous with alien spacecraft. The term "extra-terrestrial vehicle" (ETV) is sometimes used to separate this explanation of UFOs from totally earthbound explanations. A 1995 Scripps poll found 50% of Americans "believe" in UFOs, while Newsweek reported a poll where 48% opined that "reports of UFOs are real". A 2012 survey found 36% US population believe UFOs are real. A 2017 Huffpo/YouGov poll found 48% believed UFOs could be a sign of aliens visiting Earth, while only 35% rejected the idea. A 2021 Gallup poll found 41% of Americans believed some UFOs involve alien spacecraft; Pew found 51% felt UFOs are "likely evidence of intelligent life outside Earth." The prevalence of UFOs belief led University of Leicester Professor of Media Barrie Gunter to observe: "even though Ufology enthusiasts have often been dismissed as quacks, there is a silent plurality of people who believe that they might be on to something".

Identification

Studies show that after careful investigation, the majority of UFOs can be identified as ordinary objects or phenomena. The 1952–1955 study for the USAF used the following categories: "Balloon; Astronomical; Aircraft; Light phenomenon; Birds, Clouds, dust, etc.; Insufficient information; Psychological manifestations; Unknown; and Other". Identified sources of UFO reports are:

Aircraft (including military, civilian, and experimental aircraft as well as such peculiarities as aerial advertising, missile and other rocket launches, artificial satellites, the International Space Station, re-entering spacecraft including space debris, kites, and various unmanned aerial vehicles often popularly termed "drones") Astronomical objects (bright stars, bolides, bright planets, and the Moon) Balloons (surveillance balloons, toy balloons, weather balloons, large research balloons, and sky lanterns) Hoaxes Light phenomena (mirages, Fata Morgana, sundogs, ball lightning, moon dogs, satellite flares, lens flare, searchlights and other ground lights, etc.) Other atmospheric objects and phenomena (birds, unusual clouds, flares, plasma) Psychological effects (pareidolia, suggestibility and false memories, mass psychogenic disorders, optical illusions, and hallucinations)

An individual 1979 study by CUFOS researcher Allan Hendry found, as did other investigations, that fewer than one percent of cases he investigated were hoaxes and most sightings were actually honest misidentifications of prosaic phenomena. Hendry attributed most of these to inexperience or misperception. Astronomer Andrew Fraknoi rejected the hypothesis that UFOs are extraterrestrial spacecraft and responded to the "onslaught of credulous coverage" in books, films and entertainment by teaching his students to apply critical thinking to such claims, advising them that "being a good scientist is not unlike being a good detective". According to Fraknoi, UFO reports "might at first seem mysterious", but "the more you investigate, the more likely you are to find that there is LESS to these stories than meets the eye".

History

Early history before the 20th century

… excerpt ends here. Continue reading the full article.

Illustrations

Unidentified flying object illustration
Unidentified flying object: A Fata Morgana, a type of mirage in which objects located below the astronomical horizon appear to be hovering in the sky just above the horizon, may be responsible for some UFO sightings.[21]
A Fata Morgana, a type of mirage in which objects located below the astronomical horizon appear to be hovering in the sky just above the horizon, may be responsible for some UFO sightings.[21]
Unidentified flying object: Twilight phenomenon from a Falcon 9 rocket launch
Twilight phenomenon from a Falcon 9 rocket launch
Unidentified flying object: The celestial phenomenon over Basel in 1566.
The celestial phenomenon over Basel in 1566.
Unidentified flying object illustration

Worked examples

Example 1 — a first encounter with Unidentified flying object

Start with the simplest possible case. Write down what Unidentified flying object claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In physics, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Unidentified flying object before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Unidentified flying object ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Unidentified flying object

In research
Unidentified flying object appears in physics research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry
Engineering practice reuses Unidentified flying object in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom
Unidentified flying object is common in secondary-school and first-year university syllabi. It links to neighbouring topics Alleged extraterrestrial visitation, Atmospheric optical phenomena, Paranormal, so understanding it makes those chapters shorter.
In everyday life
Look for Unidentified flying object outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.
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How to study Unidentified flying object in 20 minutes

  1. Read the reference excerpt below once, without taking notes.
  2. Close the page and write down what Unidentified flying object means in your own words.
  3. Compare your version with the excerpt and mark what you missed.
  4. Work through the three examples above with pen and paper.
  5. Explain Unidentified flying object out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Unidentified flying object in simple terms?

An unidentified flying object (UFO) is an object or phenomenon seen in the sky but not yet identified or explained. The term was coined when United States Air Force (USAF) investigations into flying saucers found too broad a range of shapes reported to consider them all saucers or discs.

Why does Unidentified flying object matter?

Because it connects several physics ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Unidentified flying object?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Unidentified flying object.

Tags

  • Alleged extraterrestrial visitation
  • Atmospheric optical phenomena
  • Paranormal
  • Supernatural urban legends
  • Unexplained phenomena
  • Unidentified flying objects

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