UFOs are typically observed in the sky, but there have also been numerous sightings of objects emerging from beneath the waves.
UFOs are not an exclusively modern phenomenon - people have been seeing objects in the sky for thousands of years.
The rather unusual object was captured on camera in Jezero Crater by the Perseverance rover earlier this month.
The unidentified object, which has been likened to one of the eggs from the movie 'Alien', was found off the coast of Alaska.
An astronomical object resembling the curious symbol has appeared in the background of an image of the Vela Constellation.
Astronomers have been attempting to understand the nature of a distant object known only as GPMJ1839-10.
This incredible wireframe sculpture of a car looks more like computer graphics than it does a real physical object.
Witnesses reported a peculiar spinning object hovering in the sky over the city on Wednesday evening.
A lawyer who spoke to whistleblower David Grusch has revealed details of one of the objects recovered by the US government.
Spectators of the aerial display couldn't help noticing that something else had joined the famed aircraft for the display.
The bizarre encounter saw the terrified family call 911 to report alleged 'non-human beings' outside their home.
Sightings of an unidentified object caused considerable disruption for air traffic in southeastern Turkey last weekend.
An object spotted over the remote Pacific state prompted the US Air Force to send out 3 fighter jets last week.
The Israeli spoon bender has published footage of a mysterious object while declaring 'they are watching'.
Unidentified flying objects of various shapes and sizes were reported over parts of England during 2022, new data has revealed.
The grainy, black-and-white images show what appears to be a thin, cylindrical object flying over the city of Baghdad.
The small town of Bonnybridge in Scotland has become synonymous with sightings of unidentified flying objects.
Space policy expert Wendy Whitman Cobb takes a look at the modern UFO phenomenon and what we mean by 'UFO'.
Three unidentified objects have now been downed by fighter jets over North America and we still don't know what they are.
The mysterious object was reportedly smaller than the Chinese balloon that was shot down last week.