Diamond-shaped chunk of ice in the Caspian Sea

NASA spotted this diamond-shaped chunk of ice standing out against the blue of the 600-mile Caspian Sea that stretches from Kazakhstan to Iran. The image, taken by Landsat 8’s Operational Land Imager, shows the Caspian Sea separated by a shelf of sea ice from the Volga Delta, Europe’s largest inland river delta (the snow-dusted sediment in the upper left of the image). The diamond-shaped chunk of ice likely detached from the sea ice nearby. It sits in an expanse of thin ice called ‘nilas’, defined as a crust of ice less than 4 inches thick.