The strange phenomena, described as an orb of light inside a disk-shaped purple haze, continues to make headlines worldwide after being captured on camera.
In the latest case, The Irish Sun reported that a “bizarre UFO” was pictured in daylight above County Leitrim, which it said was a UFO hotspot.
The newspaper website described it as an “eerie snap of a UFO,” and said it had been recorded as a sighting by the Filer’s Research Institute, the US-based National UFO Center, run by Major George A. Filer, who spent 20 years in the Air Force working as an intelligence officer, and is now convinced aliens exist.
The Irish Sun warded of sceptics, saying: “Before you dismiss it as a picture of the moon at night – the image was taken in broad daylight.”
It called on astronomer Eamonn Ansbro of Kingsland Observatory in Boyle, Co Roscommon, for his view.
He said he thought the latest sighting could be a new form of light known as a plasma ball.
He said: “There’s a similar ball of light that has been seen in a place called Hessdalen in Norway.
“I know the people who operate there and they have automated instrumentation that has recorded them, and we’ve had recordings here as well.
“It appears to be a new form of light in physics that we don’t know about yet, so we’re putting the physics to it to see what it’s about.”
But, Express.co.uk can reveal that the object in question is actually a common form of lens flare – meaning there was nothing outside the camera when the snap was taken.
Lens flares occur when a camera is pointed towards strong sunlight or artificial lights.
It causes light to refract inside the camera before the anomaly in question then appears on the final image.
Despite this countless pictures showing the lens flare are sent to UFO investigation databases across the globe, and few ever appear to get removed or confirmed as lens flares.
Witnesses usually say in their report that they saw nothing at the time, but spotted the object when reviewing the images later.
This is because there was nothing in the sky at the time.
In the latest case the anonymous photographer in County Leitrim said: “The purple haze was not there or visible to the eye. I’m confused in truth.”
The US-based Mutual UFO Network (MUFON) holds the worlds largest database of UFO sightings.
It is regularly sent images showing the same lens flare, but it rarely updates its website to say they have been dismissed as such.
MUFON usually receives 20 plus reports, often including photographs or video, from people around the world each day.
We found scores of alleged UFO pictures sent in by members of the public to MUFON that were clearly or likely to be just lens flares.
In most of these cases the person filing the report said they saw nothing at the time, but spotted the “object” after later reviewing the picture.
In many situations the lens flare only appeared in one or two of a series of images.
In one case the photographer, a man from Los Gatos California, said: “As soon as we looked at the pictures, to our amazement, we had captured a strange orb with layers of colour around it in a couple of the shots.”
Despite the high volume of red-herring reports with the potential to be easily solved, MUFON lists the majority of them as still unresolved.
Although there is reference to lens flares on the MUFON website, there is no specific article highlighting the different types which people could refer to before sending in images.
We showed the County Leitrim “UFO” to Scott Brando, a forensic UFO investigator behind the website ufoofinterest.org which exposes hoaxes and false UFO sightings.
He said: “Well, this picture cropped shows just a lens flare.”
He provided examples of the same lens flare produced by cameras pointed at the sun.”
He said: “I think MUFON should have a section with typical FAQs to help people to identify correctly their alleged UFO sightings.
“Of course this means people will learn to identify a ‘flying object’ before sending a report to MUFON.”