The US Army initially announced that they had recovered a crashed "Flying Saucer", or UFO, but later changed their minds and claimed that it was a weather balloon.
Since these events in the US, millions of people worldwide have claimed to see unexplained flying objects in the skies.
In 2006, the British Ministry of Defence released papers detailing its own investigations into the UFO phenomenon. They collected over 10,000 eyewitness reports from England, Wales and Scotland, but found no evidence of any grey aliens.
The most common explanation of the sightings is sundogs (reflections from ice crystals in the atmosphere), space debris re-entering the atmosphere, weather balloons, ball lightning, meteors, mirages, even Venus being low in the sky.
But stepping back a little, the sightings started around the time of the Cold War and peaked at height of the Cold War. According to David Clarke, a lecturer in journalism, "We were projecting things to reflect our fears and concerns about the Cold War"
The UFO phenomenon is also linked with the modern reliance on conspiracy theories, a mixture of a need to believe in something more than the mundane in an increasingly rational world and an all-pervading distrust of authority.
In recent years, even with the widespread use of digital cameras and camera phones, the reports of sightings have been decreasing dramatically.
Could it be that bulk media attention of programs such as X-Files, have created an indifference towards UFO's? Or is it that in a post 9/11 world we are just more worried about terrorism that aliens?