DETECTIVE Gary Heseltine is trying to solve a mystery that has puzzled man for millennia.
The 49-year-old West Yorkshire detective constable, who works for British Transport Police in Leeds, has studied conundrums in the UK's skies for years.
Now he is the top investigator into sightings by other police officers.
Det Con Heseltine created a database to cover UFO sightings by officers both on and off duty and he has now investigated more than 330 cases involving more than 750 officers.
He has been talking about his favourite sighting in 1979 when three unsuspecting bobbies parked up for a chat and a cigarette in a quiet country lane at 3am.
He said: "One of the best to come my way was from Chiltern in the Thames Valley in 1979 involving a PC Eric Rayment and two colleagues.
"It was an amazing report."
They didn't think much of a bright white light in the distance that blurred into view for a few seconds before continuing their conversation.
"Five minutes later and suddenly the bright white light appears and it's the size of a football pitch shining a beam down the width of a football field," said the father-of-three.
"It was at an altitude of about 500 feet and was about a mile away."
After moving its beam across the landscape a remarkable thing happened.
The detective said: "There are smaller objects flying around the larger object akin to the mother ship and suddenly it's gone, as corny as it sounds."
Det Con Heseltine's interest in the paranormal was sparked when he was just 15.
And he has worked all his life in Yorkshire, the UFO capital of Britain.
He was walking his girlfriend home one evening in Scunthorpe when a white light passed over them and appeared to be causing power cuts in neighbourhoods as it flew overhead.
He raced home to warn his parents that the spooky light was coming their way. They laughed. But minutes later it appeared and their power supply was lost too.
He has had two more first hand close encounters during the last 12 years.
At about 9.15pm on August 21 1999 he was sitting in the garden of his Wakefield home watching the stars.
"I was looking at the stars when my partner drew my attention to three white lights in a triangle above the house in an arrowhead formation.
"I thought it might be one object but I could see stars between the object.
"It banked away from me and turned as one. The hairs on the back of my neck stood up.
"I don't know what it was but I know planes do not travel in that formation.
"Very few things take my breath away but that really did. I was stunned.”
Det Con Heseltine, who worked as a policeman with the RAF between 1983 and 1989, was bringing the washing in one night in April two years ago when he got his binoculars to study a flying white shape.
He said: “I saw a bright white sphere coming head on towards me with no navigational lights.
“I was bringing the washing in but I dropped it all on the floor as I ran in to get my binoculars.
“I got an aided view of it for a few seconds and it was a perfect white sphere with no engine or wings and no navigational lights.”
The officer said Britain and America were two of the world’s most secretive countries which would never admit they did not fully control their own air space.
“Ninety-five per cent of sightings will have a mundane explanation,” he said.
“But that other five per cent – that’s what I specialise in.”