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An unusual winter phenomenon has visitors to Brainerd transfixed.
The Brainerd Dispatch has video footage of a remarkable, rotating "ice circle" that formed this past weekend, which is drawing crowds of people to Upper South Long Lake.
You can watch the video here.
Facebook user Ann Scheinost also shared her own footage of the phenomenon – that video is embedded above.
The newspaper also has an explanation for what is creating the disc, courtesy of Department of Natural Resources climatologist Peter Boulay, who says the circle forms as flowing water from the Nokasippi River "creates an eddy where ice is forming."
"So you get ice forming and it gets bigger as it gets colder and then the water that is moving faster is not freezing up, so what you get in the end is this big pancake of ice that is moving slowly around in a circle. You see pancake ice on water that's moving. When the lakes are trying to freeze up this past weekend, I saw a lot of that kind of ice forming in circles."
It's not the first time ice circles have drawn interest in the Midwest – two years ago one on the Sheyenne River in North Dakota that was nearly 55 feet in diameter made its rounds on the Internet, as reported by the International Business Times.
And NBC News reported they tend to show up around flowing rivers in countries with cold climates, with spinning discs also discovered in Canada, Sweden and even England during the winter.
The International Business Times said there's another theory explaining how they are creating, saying they form at bends in rivers where rushing water breaks off a piece of established ice and then rotates, becoming smooth as it grinds against the ice surrounding it.