But the Swedish expedition team that took the plunge surfaced with more questions than answers - and certainly no solution to its origins.
The divers found that the object, which some have likened to the Millennium Falcon because of its unusual round outline, was raised about 10-13 feet above the seabed and curved in at the sides, giving it a mushroom shape.
Hefty trajectory: The Swedish diving team noted a 985-foot flattened out 'runway' leading up to the object, implying that it skidded along the path before stopping but no true answers are clear
Odd shape: The object which has a 60-meter diameter is said to be raised about 10-13 feet off the seabed and the divers compared it to the shape of a mushroom
They added that the object has 'rounded sides and rugged edges'
'First we thought this was only stone, but this is something else,' diver Peter Lindberg said in a press release.
At the center of the object, which has a 60-meter diameter, has an 'egg shaped hole leading into it from the top'.
Surrounding the hole, they found a strange, unexplained rock formation. Adding fuel to the speculative fire, they said that the rocks looked 'like small fireplaces' and the 'stones were covered in something resembling soot'.
'Since no volcanic activity has ever been reported in the Baltic Sea the find becomes even stranger,' Mr Lindberg continued.
A brief video clip of the dive was released to Swedish-language paper Expressen and can be viewed on Gizmodo.
More questions: The divers found soot-covered rocks that encircled an egg-shaped hole that went into the object at its center, and have no idea what any of it means
No clarification: The divers made their sonar discovery public but waited a year to make the dive because they had to gather enough funding and base off of weather conditions
Landing spot: The exact coordinates of the object have not been released, but it is confirmed to be somewhere at the bottom of the Botnia Gulf in the Baltic Sea between Finland and Sweden
'As laymen we can only speculate how this is made by nature, but this is the strangest thing I have ever experienced as a professional diver.'
The soot also proved cause for concern for Mr Lindberg's colleague on the Ocean X explorer team, Stefan Hogeborn.
'During my 20-year diving career, including 6,000 dives, I have never seen anything like this. Normally stones don’t burn,' Mr Hogeborn said in the release.
'I can’t explain what we saw, and I went down there to answer questions, but I came up with even more questions.'
The Ocean Explorer team's sonar pictures show that the object is a massive cylinder with a 60 metre diameter and a 400 metre-long tail deep in the Baltic Sea. A similar disk-shaped object was also found about 200 metres away
Unidentified treasure: Shipwreck divers are perplexed by the oddly-shaped object that they found at the bottom of the Baltic Sea
The sonar picture of the unidentified object resembles the famed Star Wars ship the Millennium Falcon
Another find that they saw in person for the first time was the 985-foot trail that they described 'as a runway or a downhill path that is flattened at the seabed with the object at the end of it'.
The object was first found this month last year, but because of a lack of funding and bad timing, they have were not able to pull a team together to see for themselves - just the strange, metallic outline, and a similar disk-shaped object about 200 metres away.
As it was before the recent dive, the story behind the object is anyone's guess.
'We've heard lots of different kinds of explanations, from George Lucas's spaceship - the Millennium Falcon - to "it's some kind of plug to the inner world," like it should be hell down there or something,' Mr Lindberg said.
Speaking to Fox News, he said: 'We don’t know whether it is a natural phenomenon, or an object. We saw it on sonar when we were searching for a wreck from World War I. This circular object just turned up on the monitor.
While the Ocean Explorer team is understandably excited about their potentially earth-shattering find, others are slightly more sceptical and are questioning the accuracy of the sonar technology.
In the past, such technology has confused foreign objects with unusual- but natural- rock formations.
Part of the trouble they face, however, is that they have no way of telling what is inside the supposed cylinder- whether it is filled with gold and riches or simply aged sediment particles.
They're hoping for the former, and history seems to be in their favour.
The Baltic Sea is a treasure trove for shipwreck hunters, as an estimated 100,000 objects are thought to line the cold sea's floor.
The company have created a submarine that they hope will appeal to tourists and wannabe shipwreck hunters who will pay to take a trip down to the bottom of the Baltic Sea to see for themselves.
Tourist trips: Diver Peter Lindberg is hoping to take wealthy tourists down in this submarine to see the object
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