The “miniature UFO” was discovered in Silpho Moor near Scarborough, North Yorkshire, in 1957.
The metal disc was 16 inches in diameter, weighed 22lbs and was inscribed with hieroglyphics which are similar to the wreckage of the “spacecraft” alleged to have crashed in Roswell, New Mexico in June 1947.
Inside the object was a book of 17 thin copper sheets with each sheet covered in more hieroglyphics.
Local café owner Phillip Longbottom claimed the hieroglyphics translated into a 2000-word message.
The hieroglyphics are claimed to have been sent by an alien called Ullo to warn Earth about the danger posed by its nuclear weapons with the chilling message: “You will improve or disappear.”
The remains were sent to the archives of the Science Museum in London and were only recently discovered by Dr David Clarke of Sheffield Hallam University after he gave a talk on the release of the Ministry of Defence’s UFO files at the museum.
He said: “One of the museum staff tapped me on the shoulder and asked if I was aware that ‘bits of a flying saucer’ had been kept in a cigarette tin in the museum group store for decades.
“I was absolutely amazed when later we opened the tin box and saw the wreckage.
“It was obvious these were the remains of the missing Silpho Saucer that some have claimed as Britain’s answer to the famous Roswell incident.
“It’s incredible to hear that pieces of this mystery object have been sitting in a museum archive for more than half a century.”
The remains were initially sent to the Natural History Museum in London where experts said it was probably an elaborate hoax because there was no evidence the metal had come from elsewhere in the solar system or suffered high temperatures after entering the Earth’s atmosphere.
But Air Chief Marshal Lord Dowding continued to believe the object was from outer-space.
He said he had personally examined the object in 1959 and said it was a “miniature UFO”.
Former editor of UFO Brigantia magazine Andy Roberts said the Silpho Saucer is the UK’s answer to the Roswell incident.
He said: “This is an amazing breakthrough. It’s incredible to hear that all this time pieces of this mystery object have been sitting in a museum archive.”
Scarborough have received several reports of UFO sightings in the past.
Witnesses reported seeing strange lights, and odd-shaped craft in an area from Brandesburton in East Yorkshire to Scarborough, North Yorkshire, between May and September 2009.
In some cases UFOs were seen entering the sea, and cars ground to a halt as one appeared, it is claimed.
Two Chinook helicopters full of RAF personnel landed at the beach by the remote hamlet of Wilsthorpe, East Yorkshire, on Tuesday, September 15 2009, at the height of the sightings, paranormal researcher Paul Sinclair has revealed.
It was the day after a bizarre late-night sighting of between 30 and 40 UFOs in the same area by an elderly couple whose home overlooked the beach, he said.
The multiple UFO sightings followed a spate of other strange UFO encounters along the area of coastline, Mr Sinclair told the Outer Limits Magazine 70 Years of the Modern UFO Era conference in Hull.
The military action and UFOs were witnessed by the couple, two bait diggers, and a boat worker, a seven-year investigation by Mr Sinclair has discovered.