1. 1947 Roswell crash: UFO proponents claimed that the US military had captured a crashed alien aircraft. This well-publicised, controversial incident
became a pop culture phenomenon.
Explanation: the US military maintained that it had recovered debris from an experimental high-altitude surveillance balloon belonging to a classified
programme named “Mogul”.
2. 1947 Kenneth Arnold case: the press coined the term “flying saucer” after this American businessman and pilot claimed he had seen nine objects
flying in a chain near Mount Rainier, Washington. Arnold described them as saucers skipping across water.
Explanation: The US Air Force formally listed the case as a mirage.
3. 1952 Washington, D.C. flap: this series of UFO reports was accompanied by radar contacts at three separate airports. Country-wide headlines spurred
the formation of the CIA Robertson Panel.
Explanation: the US Air Force suggested that a temperature inversion - in which a layer of warm, moist air covered a layer of cool, dry air closer to
the ground - had caused radar signals to bend and give false returns.
4. 1957 Levelland case: police investigated numerous motorist reports of engines stalling when encountering a glowing, egg-shaped object. Motorists
claimed that their vehicles had restarted after the "object" had left.
Explanation: an air force investigation concluded that an electrical storm had caused the sightings and vehicle failures.
5. 1966 Westall encounter: more than 200 students and teachers at two schools in Melbourne allegedly saw a UFO that descended into a grass field. The
object then ascended over a local suburb, according to reports. Witnesses still gather for reunions.
Explanation: Australian Skeptics, a non-profit organisation which investigates paranormal and pseudo-scientific claims by using scientific
methodologies, believed that the object was an experimental military aircraft.
6. 1967 Shag Harbour crash: a large object crashed into Shag Harbour, Nova Scotia.
Explanation: The Canadian Department of National Defence officially classified this sighting as unsolved following a naval search and investigation.
The Condon Committee, which investigated UFOs at the University of Colorado, failed to resolve the case.
7. 1976 Tehran incident: A UFO was believed to have disabled the electronic equipment of two F-4 interceptor aircraft as well as ground control
equipment. The Iranian generals involved said on public record that they had thought the object was extraterrestrial.
Explanation: UFOs: The Public Deceived, a book by Philip Klass, claimed that witnesses saw an astronomical body - probably Jupiter - and pilot
incompetence and equipment malfunction accounted for the rest.
8. 1986 São Paulo chase: around 20 UFOs were seen and detected by radar in various parts of Brazil. They reportedly disappeared as five military
aircraft were sent to intercept them.
Explanation: Geoffrey Perry, a British space researcher, attributed the incident to debris that were ejected by Soviet space station Salyut-7 and
re-entered Earth’s atmosphere around central-western Brazil.
9. 1989/1990 Belgium wave: around 13,500 people claimed to have witnessed large, silent, low-flying black triangles. Around 2,600 filed written
statements describing what they had seen. The frequently-photographed wave was tracked by NATO radar and jet interceptors and investigated by
Explanation: Renaud Leclet, a French ufologist, believed some of the sightings could have been explained by helicopters.
10. 2008 Turkey video: a night guard at the Yeni Kent Compound claimed he had videotaped multiple UFOs over a period of four months. Reported witness
confirmations spurred claims by Sirius UFO Space Science Research Center it was the “most important images of a UFO ever filmed”.
Explanation: Turkish scientists claimed it was a computer-animated hoax.
Some laughable explanation..