Now explorers believe they are one step closer to discovering the truth behind the mysterious 140,000-year-old Baltic Sea Anomaly. Bearing a striking resemblance to the Star Wars Millennium Falcon, the Baltic Sea Anomaly appears to be formed of pieces of angular metal – prompting claims it is a crashed UFO. Swedish explorer Peter Lindberg and his Ocean X team of marine explorers discovered the strange object during a dive searching for an old shipwreck. Instead he discovered the so-called Anomaly.

The Truth Is Out There: 150 years of UFOs Mon, July 3, 2017 Although many UFO sightings often have rational explanations, a small number truly are unexplained. Here's our pick of the most compelling UFO sightings from all over the world Play slideshow Getty Images 1 of 27 Flying saucer above highway, real or not?

The Baltic Sea Anomaly continues to baffle oceanographers

Denis Asberg, who made the discovery alongside Mr Lindberg, told TV4 in Sweden: “There is a mountain, It could be 20-25 metres tall with a canyon in the middle, and below it there is a lot of loose rocks. “The trail starts from here. Actually there is two trails. There is the one that leads to this large circle. Then there is another trail that leads to the second object which is about 200 metres from the round circle. We found it at the same time as the circle. But we had such focus on the circle that we have not had enough time to look at the other object. It is not circular. “We were really surprised and puzzled. We were thinking what is that we have found here. This is not a wreck. At that time we thought for sure there was a natural explanation. “We wanted to look into it some more and decided to keep this totally quiet. We contacted geologists, marine biologists and when they said they had never seen anything like this, of course more thoughts were triggered. It could be something really awesome that we’ve found.”

Even more intriguingly a structure that looks like a staircase appears to lead to a dark hole with a second structure found nearby. Speculation is rife over what the object could be with some saying it could be an anti-submarine device left over from World War Two, a battleship gun turret or indeed a flying saucer. Despite looking like a huge rock, scientists say the structure appears to be made of metal. Electric and satellite diving equipment reportedly cuts out when near the object.

Anything electric out there, and the satellite phone as well, stopped working when we were above the object Diver Stefan Hogerborn

Stefan Hogerborn, a professional diver with Ocean X, said: “Anything electric out there, and the satellite phone as well, stopped working when we were above the object, then when we got away about 200 metres, it turned on again.” Mr Lindberg’s Ocean X team are continuing to investigate the object, five years after making the initial discovery while exploring the floor of the Bothnian Sea between Sweden and Finland. Sonar has found drag marks behind the object and geologist Steve Weiner says according to his tests, the structure is not a geological formation.

An Ocean X interpretation of what the Baltic Sea Anomaly may look like based on their data

The Baltic Sea Anomaly bears a striking resemblance to the Millennium Falcon

He said the object is made of “metals which nature could not reproduce itself”. Sat nearly 300ft below the surface and measuring 26ft tall, the marine explorers found the strange craft with a side-scan sonar. Mr Lindberg said: “I have been the biggest sceptic, I was kind if prepared for finding just stone. For me it has been an amazing experience. “I think it is very odd in its shape. It is tough to give an explanation as to what it might be exactly, since different scientists have many different theories. “Whatever it is, it is something we do not usually find in nature sitting in the dark cold depths of the Baltic Sea.”

The formation was found on the seabed of the Baltic Sea

Ocean X found the Baltic Sea Anomaly with a side-scan sonar

It is thought the object could be at least 140,000 years old after a university professor linked the mysterious disc to the Ice Age. Volker Bruchert, an associate professor of geology at Stockholm University, said: “My hypothesis is that this object, this structure was formed during the Ice Age many thousands of years ago.” Ocean X is expected to return to the wreck to continue investigating the discovery. Mr Lindberg said: "We will pretty much just be able to do the same things as we did in 2012. It is not for sure yet but since we're involved in a new TV project it might give us the opportunity."

The Truth Is Out There: 150 years of UFOs Mon, July 3, 2017 Although many UFO sightings often have rational explanations, a small number truly are unexplained. Here's our pick of the most compelling UFO sightings from all over the world Play slideshow Getty Images 1 of 27 Flying saucer above highway, real or not?