We've seen pictures of mysterious crop circles in fields — but what about circles in the ice on a pond?
These perfect circles appeared in the surface ice of a pond in Eden, New York - and no one seems to be able to agree on what might have caused them.
Local resident Peggy Gervase took a photo of the circles and posted them onto Facebook. After a link to the TV station WGRZ the photos began to cause a real stir, with 40,000 views and hundreds of people leaving comments as to the cause of the phenomenon - including aliens (of course!), elephants walking across the pond, meteorites, geese with bad wind and fish swimming in a circle under the ice.
Other explanations include gases rising from rotting vegetation in the pond or that the ice holes are areas where underground springs have created small currents in the pond, moving the water just enough to stop it freezing.
You can watch a news report on the WGRZ website.
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