An unidentified flying object (UFO), or unidentified anomalous phenomenon (UAP), is any perceived aerial phenomenon that cannot be immediately identified or explained. Upon investigation, most UFOs are identified as known objects or atmospheric phenomena, while a small number remain unexplained.
Donald Edward Keyhoe was an American Marine Corps naval aviator, writer of aviation articles and stories in a variety of publications, and tour manager of aviation pioneer Charles Lindbergh.
UFO conspiracy theories are a subset of conspiracy theories which argue that various governments and politicians globally, in particular the United States government, are suppressing evidence that unidentified flying objects are controlled by a non-human intelligence or built using alien technology. Such conspiracy theories usually argue that Earth governments are in communication or cooperation with extraterrestrial visitors despite public disclaimers, and further that some of these theories claim that the governments are explicitly allowing alien abduction.
Raymond Alfred Palmer was an American author and editor of science fiction magazine Amazing Stories from 1938 through 1949. Palmer wrote science fiction and fantasy stories, some of which were published under pseudonyms. After leaving Amazing Stories, he published and edited the magazines Fate, Mystic,Search,Flying Saucers, and others. He established his own publishing house, Amherst Press and Palmer Publications, and published or republished spiritualist books, including Oahspe: A New Bible, and books related to flying saucers, including The Coming of the Saucers, co-written by Palmer with Kenneth Arnold.
Kenneth Albert Arnold was an American aviator, businessman, and politician.
The extraterrestrial hypothesis (ETH) proposes that some unidentified flying objects (UFOs) are best explained as being physical spacecraft occupied by extraterrestrial intelligence or non-human aliens, or non-occupied alien probes from other planets visiting Earth.
The "Maury Island incident" refers to claims made by Fred Crisman and Harold Dahl of falling debris and threats by men in black following sightings of unidentified flying objects in the sky over Maury Island in Puget Sound. The pair would later claim the events had occurred on June 21, 1947.
The Flying Saucers Are Real by Donald Keyhoe, was a book that investigated reports of UFOs by United States Air Force fighters, personnel, and other aircraft, between 1947 and 1950.
Project Sign or Project Saucer was an official U.S. government study of unidentified flying objects (UFOs) undertaken by the United States Air Force (USAF) and active for most of 1948. It was the precursor to Project Grudge.
In ufology, conspiracy theory, science fiction, and comic book stories, claims or stories have circulated linking UFOs to Nazi Germany. The German UFO theories describe supposedly successful attempts to develop advanced aircraft or spacecraft prior to and during World War II, further asserting the post-war survival of these craft in secret underground bases in Antarctica, South America, or the United States, along with their creators.
A flying saucer is a descriptive term for a type of flying craft having a disc or saucer-shaped body, commonly used generically to refer to an anomalous flying object. The term was coined in 1947 but has generally been supplanted since 1952 by the United States Air Force term unidentified flying objects. Early reported sightings of unknown "flying saucers" usually described them as silver or metallic, sometimes reported as covered with navigation lights or surrounded with a glowing light, hovering or moving rapidly, either alone or in tight formations with other similar craft, and exhibiting high maneuverability.
The Kenneth Arnold UFO sighting occurred on June 24, 1947, when private pilot Kenneth Arnold claimed that he saw a string of nine, shiny unidentified flying objects flying past Mount Rainier at speeds that Arnold estimated at a minimum of 1,200 miles an hour (1,932 km/h). This was the first post-World War II sighting in the United States that garnered nationwide news coverage and is credited with being the first of the modern era of UFO sightings, including numerous reported sightings over the next two to three weeks. Arnold's description of the objects also led to the press quickly coining the terms flying saucer and flying disc as popular descriptive terms for UFOs.
The Twin Falls saucer hoax was a hoaxed flying disc discovered in Twin Falls, Idaho, United States, on July 11, 1947. Amid a nationwide wave of alleged "flying disc" sightings, residents of Twin Falls reported recovering a 30 in (76 cm) "disc". FBI and Army officials took possession of the disc and quickly proclaimed the object to be a hoax. Press reported that local teenagers admitted to perpetrating the hoax.
They Knew Too Much About Flying Saucers is a 1956 book by paranormal author Gray Barker. It was the first book to allege that "Men in Black" were covering up the existence of flying saucers.
The Flight 105 UFO sighting occurred on July 4, 1947, when three crew members aboard a United Airlines flight reported seeing multiple unidentified objects in the skies over the Pacific Northwest. A week prior, private pilot Kenneth Arnold had reported seeing similar objects nearby – a sighting that was followed by nearly 800 "copycat" reports during the summer of 1947. Four days after the Flight 105 sighting, Roswell Army Air Field issued a press release stating that they had recovered a "flying disc"; that statement was quickly retracted after the crashed object was identified as a conventional weather balloon. The following month, on July 29, an air crew flying the same route also reported unidentified objects.
The 1947 flying disc craze was a rash of unidentified flying object reports in the United States that were publicized during the summer of 1947. The craze began on June 24, when media nationwide reported civilian pilot Kenneth Arnold's story of witnessing disc-shaped objects which headline writers dubbed "Flying Saucers". Such reports quickly spread throughout the United States; historians would later chronicle at least 800 "copycat" reports in subsequent weeks, while other sources estimate the reports may have numbered in the thousands.
The Rhodes UFO photos, sometimes called the shoe-heel UFO photos, are two photos that were reportedly taken on July 7, 1947 by amateur astronomer and inventor William Albert Rhodes. The photographs purport to show a disc-like object flying above Phoenix, Arizona. Rhodes's account and photographs were published by the Arizona Republic on July 9.
The Flying Saucer Conspiracy is a 1955 book authored by early UFO researcher Donald Keyhoe. The book pointedly accused elements of United States government of engaging in a conspiracy to cover up knowledge of flying saucers. Keyhoe claims the existence of a "silence group" of orchestrating this conspiracy.
The Report on Unidentified Flying Objects is a 1956 book by then-retired Air Force UFO investigator Edward J. Ruppelt, detailing his experience running Project Bluebook. The book was noted for its suggestion that a few UFO sightings might be linked to spikes of atomic radiation. Contemporary media summarized four topics discussed in the book:
