In June 2011, Peter Lindberg, Dennis Åsberg, and their Swedish OceanX diving team found a blurred sonar picture while searching for treasure on the floor of the northern Baltic Sea in the center of the Gulf of Bothnia. They believed the image showed an object with unusual features that did not look like natural formations, leading to reports in tabloid newspapers that the object might be a sunken UFO. Most scientists and experts agree that the image likely shows a natural geological formation.

History

OceanX, a group based in Sweden, describe themselves as people who search for valuable items and recover lost objects from the sea. In the summer of 2011, during an expedition in the Baltic Sea between Sweden and Finland, the team found a "blurry but interesting" sonar image while looking for an old shipwreck. They say the image shows a circular object about 200 feet in diameter with features that might be man-made. The group returned to the site the next year to collect more detailed sonar scans. After a story about the discovery was published in the UK newspaper Daily Mail in June 2012, many wild theories about the object became popular.

OceanX gave samples of stone found at the site to Volker Brüchert, a professor of geology at Stockholm University. Brüchert’s analysis showed that most of the samples were made of granite, gneiss, and sandstone. One sample was a piece of basaltic (volcanic) rock, which is common on the site but unusual for the seafloor. Brüchert explained that the northern Baltic region is heavily affected by melting glaciers and the processes that happen after glaciers melt. He suggested that the rocks may have been carried to the area by glaciers.

Swedish geologists Fredrik Klingberg and Martin Jakobsson noted that the chemical makeup of the samples is similar to nodules often found on the seafloor. They said that materials like limonite and goethite can naturally form in the ocean. The geologists did not have samples from the object itself, only from the seafloor and surrounding area.

Response

OceanX shared one sonar image, but many people criticized it. Hanumant Singh from Woods Hole Oceanographic Institution said the image is not reliable because distortions make it hard to see underwater shapes. Singh explained that the image's problems came from a low-quality sonar device that was not set up correctly. An MSNBC article suggested that seeing a flying saucer in the image might be because tabloid newspapers added outlines of the Millennium Falcon, a fictional spaceship.

Charles Paull from the Monterey Bay Aquarium Research Institute said the unclear image might show a rock formation, sediment from a fishing boat, or a group of fish. Paull called the story "curious and fun, but not very important."

Göran Ekberg, a marine archaeologist in Stockholm, said a natural rock formation might be the cause. He agreed the shape looks strange but noted that nature can create unusual shapes. Martin Jakobsson, a professor at Stockholm University, guessed the image might show sandstone. He said he needs more information before giving an official opinion. Other experts think the image could show rocks from glaciers, pillow basalt, or a moraine.

Jarmo Korteniemi, a Finnish scientist, said volcanic explanations like hydrothermal vents are unlikely in the area because there's no active volcanism. He explained the "runway" shape is probably a natural rock formation shaped by glaciers.

Jonathan Hill from the Mars Space Flight Facility questioned OceanX's plans to take rich tourists to the site. He said in 2012 that people making big claims should be checked to see if they have a personal gain. He also said it would be easy to take a sample for testing, and if it was just rock, that wouldn't help Peter Lindberg.

In a 2019 interview, Lindberg said there might be a new expedition through a TV production they are involved in.