Whether there really is alien life lurking in outer-space there is something that has baffled experts for generations.
But one man claims to have captured proof that not only do extra-terrestrials exist, they have also entered Earth's atmosphere.
Alan Kingwell seems to have captured something truly bizarre on his camera while sat in his back garden in Plymouth.
The 62-year-old decided to shoot a timelapse video of the clouds after seeing how dramatic the sky was.
But it was only when he went to edit the film that he noticed two strange, flying objects motionless in the sky.
The black blobs don't move with the clouds
Sometimes, they are covered by clouds but as they pass forward, the black blobs are clearly in view.
"It was filmed accidentally and I never saw the objects until I edited the timelapse film," he said.
"I immediately tried lots of things to dismiss camera error or any other natural things that may have caused this."
At first he assumed it was a fault with his lens or with his camera , but quickly dismissed these suggestions.
He told Cornwall Live: "I spend many hours looking at the tiny clip and I am convinced now that there really was something totally motionless high in the sky.
The sky looks gorgeous - but on closer look, you can see something else is going on
"There is a part of the clip where you can see the two objects being covered by cloud and peeping through again to be covered once more before they are revealed again when the cloud disperses."
After the discovery, the artist went back out armed with binoculars and a better camera but the clouds had become thicker.
"I spotted something through the binoculars for a few seconds before the clouds covered it," he said.
"I immediately phoned my good lady to come out and see but the cloud covered the sky completely and it was like that all evening.
The circular black dots have left the artist baffled
"Such a shame because I think these two objects were still there at that time which by then would have been around 6.15pm but the cloud cover was too much."
Alan went back out at dawn the next morning to study the sky with binoculars but there was nothing there.
"I have been looking at the sky ever since," he said. "I have always had an open mind and been fascinated with things like this and was so pleased to have captured these two objects, whatever they are.
"I have also sent the clip in to various societies who were studying this kind of thing and they are very intrigued."
Alan a self employed artist, is now appealing for witnesses and asked if anyone else in the area saw something strange in the sky on August 30, around 5 to 6pm. You can get in touch here.