The oddly satisfying phenomenon was discovered near the Larden C ice shelf in the Antarctic Peninsula.
From yesterday's #IceBridge flight: A tabular iceberg can be seen on the right, floating among sea ice just off of the Larsen C ice shelf. The iceberg's sharp angles and flat surface indicate that it probably recently calved from the ice shelf. pic.twitter.com/XhgTrf642Z— NASA ICE (@NASA_ICE) October 17, 2018
It shows a thick bloc of ice up to a mile long dramatically protruding from a sea of thin frozen water, thought to have recently splintered off.
Scientists took the snap from a plane used to monitor changing land and sea ice in the South Pole.
Many have remarked about its peculiar shape, with some suggesting the work of Photoshop or aliens.
But NASA ice scientist Kelly Brunt explained the process that caused it is fairly common.
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She said there were two types of iceberg.
The most familiar are those that look like prisms, such as the one that sank the Titanic.
The second are called "tabular icebergs", Ms Brunt said, comparing their formation to a fingernail growing too long and breaking off at the end.
"What makes this one a bit unusual is that it looks almost like a square," she told the LiveScience website.
The size was hard to guess, Ms Brunt said, but suggested it was likely more than a mile long.
And as with all icebergs only 10% of it is visible; the rest if buried below the surface of the water.
That was not the only shape that scientists spotted last Wednesday.
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A triangular iceberg was also seen nearby, surrounded by several different types of sea ice.
Sea ice comes in many types and forms, depending on the stage of development and the meteorological, atmospheric, and other physical conditions.