Do aliens exist? This question has baffled humans for centuries.
From Roswell to Suffolk's Rendlesham Forest, these are the sightings which UFO hunters have hailed as proof of extra-terrestrial life.
How many alien and UFO sightings have there been?
The number of UFO sightings is currently flying at an all-time high, according to data cruncher and blogger Sam Monfort.
The alien expert reckons there have been nearly 105,000 recorded UFO sightings in the past 100-plus years.
And Sam is far from the only believer on our planet.
From an "alien autopsy" video dating back to 1995 to a video of fighter jets apparently chasing a UFO over the M5, there are hundreds of videos which people have claimed to be proof of alien life.
There's even a clip of a UFO supposedly attacking a Taliban compound, as well as 'sightings' in Peckham and Warminster.
Most of the videos have been debunked by experts. In the M5 clip, for example, the motorway lorries look like models.
While the Peckham UFOs were "almost certainly Chinese lanterns", former Ministry of Defence UFO investigator Nick Pope told the Sun Online.
This story originally appeared in The Sun.