The mysterious 'crafts' have been spotted over an iceberg, an airport and even a Cornish holiday resort.
There has been something of a glut of UFO and alien sightings over the past few months.
With that in mind, here is our look back at some of the close encounters that have been making the headlines in 2014.
Remember: the truth is out there.
1) UFO spotted hovering over iceberg in eastern Canada
An eyewitness claimed to have spotted a white object spinning and shape-shifting above the sea during an excursion to Salvador, Newfoundland.
2) US Army Air Force fighter jet destroys giant 'alien monster' in desert
A video uploaded to YouTube purports to to show the moment a fighter jet bombs a bizarre, throbbing jellyfish-like object in New Mexico, in the United States.
3) UFO whizzes past CCTV camera on darkened industrial estate
In this video, a bright, white object can be seen hurtling through the air at breakneck pace. It was recorded on a CCTV camera on an industrial site in Prokopyevsky, Russia.
4) UFO attacks Taliban camp in Afghanistan
This clip shows a triangular shaped airborne object open fire on an insurgent position. Explosions can be seen and a huge plume of smoke soon rises up in to the sky.
5) Bizarre 'rotating' object spotted over London
A series of photographs showed a black, rotating object complete with a light in the skies above the capital. It later floated off in the direction of Highbury and Islington
6) Mysterious UFO 'attempts to communicate with stunned deer'
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Stills from a night-time 'deer-cam' showed two parallel beams of light in the background behind a startled deer. Camera owner EDith Shattles said: "It was something I've never seen before."
7) Bizarre triangular objects spotted flying in formation over Texas
Plane spotter Steve Douglass saw the craft alongside two others and took a photo - moments after claiming to have listened in to a conversation between two pilots.
8) Amateur photographer snaps mystery 'aircraft' streaking across the sky in Cornwall
Granddad Michael Potter photographed the 'blazing triangular shape' above the seaside holiday resort of Mounts Bay. He said: "The photo hasn't been photo-shopped or tampered with, so what is it the mysterious object?"
9) Bizarre UFO spotted by robot on surface of MARS
The 'spacecraft complete with vapour trail' was photographed by an unmanned Nasa rover at work on the surface of the Red Planet.
10) UFO spotted above airport causes flights to be cancelled and delayed
The object was spotted on radars at Germany's Bremen Airport but despite a police helicopter being scrambled, nothing was found.