A team of Swedish deep sea explorers have discovered a large, round shaped object on the 300-foot-deep ocean floor between Finland and Sweden. The discovery has sparked off several speculations.

Sweden's Ocean Explorer, an ocean exploration team that hunts for sunken ships and cargo, made the discovery inadvertently while hunting for a century-old shipwreck that had several cases of rare champagne. The team, led by Peter Lindberg, was using sonar to survey the Gulf of Bothnia last month while looking for the shipwreck. Lindberg noticed a "a large circle, about 60 feet in diameter" while studying the sonar scans.

"You see a lot of weird stuff in this job, but during my 18 years as a professional I have never seen anything like this. The shape is completely round," Lindberg told local media.

There was evidence of scars and marks disturbing the earth nearby, suggesting that the object moved across the ocean floor to where the team found it, added Lindberg.

While there is no clear explanation as to what the object could be, its discovery has triggered a lot of different viewpoints. UFO enthusiasts believe it could be an extraterrestrial spacecraft that crashed, thereby dislocating the earth around it.

However, it could be a natural feature formation like the rim of a small underground volcano, or even a sunken round man-made object. Lindberg himself suggested that it could be a "new Stonehenge."

Moreover Lindberg's claims that the object is "completely round" may or may not be accurate as the sonar images were not very clear to verify this, reports Fox News. Besides the scars leading to (or from the feature) may suggest some kind of movement, it is also possible that they have nothing to do with the object, added the report.

Till the shape is examined further there is no clear explanation for it. However, Lindberg said that since the object could turn out to be completely worthless they could not afford to spend funds on examining it further.

This is not the first time an unidentified sunken object has led to conjecture. There is the famous underwater mystery of 'Bimini Road', a rock formation in the Caribbean that resembles a road. Even though geologists have said that the rocks are naturally formed, there are theorists who link the formation to an unknown civilization or to the lost city of Atlantis.

In fact, the possibility of the existence of aliens has captivated people for years. In the United States, most UFO stories and sightings usually come from the Southwest. The rational explanation to this is that the Groom Lake Air force base is located here. This is not a conventional airbase as front line units are not normally deployed there. It is mostly used for developing and testing new aircraft and its operations are shrouded in secrecy. The federal government concedes that the U.S. Air Force has an “operating location” near Groom Lake, but does not provide any further information.

Since the base develops latest aircraft and conducts secret tests unknown to the public, it is very likely that UFO sightings linked to aliens are in reality some latest technologically advanced aircraft being tested at the base. For instance the B-2 Bomber was flown numerous times in that area before it was made public. The bomber aircraft’s wing design was very unique and almost made it look like a saucer. For a layman, it might look like an extraterrestrial flying object. Moreover, most of the tests take place at night. Factors like night test flights, secret operations, lack of knowledge about fighter jets and aircraft lead to the emergence of UFO conspiracy theories in this area, say experts.

See pictures and videos of the mysterious object on the Ocean Explorer's Web site.