Is anybody out there? The MOST famous UFO sightings

The age-old debates over those unidentified flying objects, better known as UFOs, have left some mysterious question marks lingering in the minds of people through generations.

Although several reports of alleged alien abductions to those intriguing flying objects have been dismissed from time to time, UFO believers have not yet received a convincing answer to the undying question: Is anybody out there?

We present a collection of 20 famous UFO sightings across the world, as reported in the Stylist.

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The Roswell UFO incident was a report of an object that crashed in the general vicinity of Roswell, New Mexico, United States 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 conspiracy theories as to the true nature of the object that crashed. The United States Armed Forces maintains that what was recovered was debris from an experimental high-altitude surveillance balloon belonging to a classified program named "Mogul", however, many UFO proponents maintain that an alien craft was found and its occupants were captured, and that the military then engaged in a cover-up.

The Kenneth Arnold UFO sighting was an incident on June 24, 1947, where private pilot Kenneth Arnold claimed he spotted a string of nine, shiny UFOs flying past Mount Rainer in Washington at then unheard of supersonic speeds that Arnold clocked at a minimum of 1,200 miles an hour. Not surprisingly, the media had a field day over the 'flying saucer' incident.

However, based on subsequent analysis, investigator Philip J Klass concluded that Arnold may have seen a fireball bolide breaking up as it traveled through the Earth's atmosphere.

The 1952 Washington, DC UFO incident was a series of unidentified flying object reports from July 12 to July 29, 1952, over the US capital.

"The CIA Robertson Panel was formed after reports of UFOs appearing in the skies above Washington were convincingly backed up by mysterious radar contacts at three separate airports. However, the US air force allayed fears of an alien invasion, suggesting that changes in the temperature had caused radar signals to bend and give false returns," the report states.

Betty and Barney Hill were an American couple who claimed to have been abducted by extraterrestrials in a rural portion of New Hampshire, US on September 19-20, 1961. Theirs was the first widely-publicised claim of alien abduction.

According to the couple, they had been followed by a flying saucer while driving in their car, abducted and then subjected to an intimate physical examination. They also recall observing a 3D 'star map' inside the ship. Even under hypnosis, the Hill's maintained their story and aroused massive interest and publicity, the report states.

The Rendlesham forest incident is the name given to a series of reported sightings of unexplained lights and the alleged landing of a craft or multiple craft of unknown origin in Rendlesham Forest, Suffolk, England, in late December 1980, just outside RAF Woodbridge, used at the time by the US air force.

Dozens of USAF personnel were eyewitnesses to various events over a two- or three-day period.

The authorities insist there was nothing mysterious going on and no risk to national security, however, as the witnesses were on-duty servicemen, the reports were given a measure of credibility, and a belief persists that the lights were from an alien spacecraft.

Eminent American astronomer Clyde W Tombaugh poured cold water on the consensus that most UFO sightings were recorded by publicity-seekers, when, two years after Roswell, Tombaugh recorded seeing up to eight rectangular lights in the sky above Las Cruces in New Mexico, and on another occasion several green fireballs.

"As a serious-minded astronomer used to studying the skies (one of his greatest achievements was the discovery of the dwarf planet Pluto in 1930), his inability to explain the lights made his claims particularly hard to dismiss," the report states.

The Levelland UFO case occurred on November 2-3, 1957, in and around the small town of Levelland, Texas, US.

Drivers in Levelland, Texas reported that their car engines stalled when encountering a glowing, egg-shaped object, and then mysteriously restarted again after the object had left.

A police investigation followed and it was concluded that an electrical storm had caused the sightings and vehicle failures, the report states.

The Shag Harbour UFO incident was the reported impact of an unknown large object into waters near Shag Harbour, a tiny fishing village in the Canadian province of Nova Scotia on October 4, 1967.

A search and investigation was conducted, but later classified as unsolved by the Canadian Department of National Defence when a clear conclusion could not be reached.

Sailor Harold Dahl experienced a run-in with the real 'men in black', after claiming to have seen six UFOs while scavenging for driftwood in Washington's Puget Sound.

The next day he was approached by an unknown, black-suited individual who warned him off repeating his story with threats against his family. However, it's unclear whether the UFO incident was actually real or a secret military exercise which had gone wrong.

The Westall UFO encounter is an event that occurred on April 6, 1966 in Melbourne, Australia. Around 11 am, for about 20 minutes, more than 200 students and teachers at two Victorian state schools allegedly witnessed an unexplained flying object which descended into a nearby open wild grass field.

The paddock was adjacent to a grove of pine trees in an area known as The Grange. According to reports, the object then ascended in a north-westerly direction over the suburb of Clayton South.

Lonnie Zamora, a New Mexico police officer, reported a UFO sighting while on duty on Friday, April 24, 1964, near Socorro, New Mexico.

Zamora saw a huge, bluish-orange flame in the sky south of Socorro, and went to investigate. The flame was accompanied by a deafening roaring sound, and as Zamora drew nearer he saw a weird, doughnut-shaped silver machine and two white-clad individuals.

"Although the pair quickly flew off, Zamora's detailed testimony has provided one of the most comprehensive accounts of an alien encounter, and is often cited as a significant spur in persuading the US air force to take the growing numbers of UFO sightings more seriously," the report states.

Two senior US military pilots claimed to have spotted three aircraft of a type unknown to them while flying in a North American B-25 Mitchell bomber over the Carson Desert.

They said the three unidentified objects were moving about three times faster than their B-25. While the B-25 wasn't known to be a particularly fast machine, both men insisted that the three crafts were not a new type of super-fast jet.

"60 years later the sighting is still officially classified as unexplained," the report states.

Military aircraft were sent to intercept around 20 UFOs detected by radar in various parts of Sao Paulo, Brazil, on May 23, 1986.

However, once the military began to give chase, the mysterious objects reportedly disappeared. Providing one solution to the incident is Geoffrey Perry, a British space researcher. He put the sighting down to debris that were ejected by Soviet space station Salyut-7 re-entering the Earth's atmosphere around central-western Brazil, the report adds.

Before becoming the President of US, Jimmy Carter, then governor of Georgia, reportedly saw a UFO while at Leary.

Carter was asked to file a report of the sighting by the International UFO Bureau in Oklahoma City, Oklahoma, which he did in September 1973.

Since its writing, the report has been discussed several times by both ufologists and by members of the mainstream media. Carter does not think that it was an alien spacecraft.

Carter said he had seen a strange white light in the evening sky. He claimed he watched it change from white to blue, and then to red, before changing back to white and appearing to gradually fade off into the distance.

The 1976 Tehran UFO Incident was a radar and visual sighting of a UFO over Iranian capital Tehran, during the early morning hours of September 19, 1976.

During the incident, two F-4 Phantom II jet interceptors supposedly lost instrumentation and communications as they approached, only to have them restored upon withdrawal; one of the aircraft also supposedly suffered temporary weapons systems failure, while preparing to open fire.

The incident, recorded in a four-page US Defence Intelligence Agency report, remains one of the most well-documented military encounters with anomalous phenomena in history, and various senior Iranian military officers directly involved with the events have gone on public record stating their belief that the object was not of terrestrial origin.

The Lubbock Lights were an unusual formation of lights seen over the city of Lubbock, Texas, from August-September 1951.

Three professors from Texas Technical College spotted an unusual light formation flying over Lubbock. The 20 to 30 lights flew in a 'V' shape over the town, and the occurrence was eventually photographed by a student from the college with the photographs later appearing in Life Magazine, although an explanation of the sightings is yet to be found.

Between 1989 and 1990, around 13,500 people claim to have observed large, silent, low-flying black triangles in the skies above Belgium, with 2,600 written statements on file about what they had seen.

"The frequently-photographed wave was also tracked by NATO radar and jet interceptors and investigated by Belgium's military, although some put the sightings down to ordinary helicopters," the report states.

The 2008 Turkey UFO sightings were a series of videotaped and documented UFO sightings by the 42-year-old Yalcin Yalman, a night guard in Turkey.

They occurred between May and September 2008, mostly while the sky was dark (between 8 pm and 5 am), though some of the video is taken at dawn, out over the Sea of Marmara. This case has been welcomed with open arms by the Sirius UFO Space Science Research Center in Turkey, calling the video "the most important UFO images ever."

The Berwyn Mountain Incident was an alleged "UFO crash" on the Berwyn Mountains in Llandrillo, Merionethshire, North Wales in Britan, which took place on January 23, 1974.

Like the Roswell incident 27 years earlier, rumours of the UFO crash in followed after reports of shaking ground and strange lights in the sky. Investigations began and Gwynedd police recorded a statement from a witness who claimed to have seen a "bright red light, like coal fire red. Large perfect circle. Like a big bonfire. Could see lights above and to the right and white lights moving to bottom. Light changed colour to yellowish white and back again."

No remains were found and the unsteady ground was likely to have been caused by the Bala Earthquake which hit the area that night, but several locals still insist they saw a glowing, egg-shaped craft, the report states.

When radar picked up an unidentified flying object over the North Sea, pilots quickly attempted to make contact.

"Captain William Schaffner intercepted a 'conical object' then all contact with him was lost. Three months later his plane was discovered undamaged on the seabed, but his body was never recovered. However, official reports eschewed the idea of an extra-terrestrial mystery, deeming the pilot's likely death being caused by flying too low over the sea," the report states.

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