Number 277 (Story #3), July 1, 1996 by Phillip F. Schewe and Ben Stein A LARGE LAKE BENEATH THE ANTARCTIC ICE SHEET has been pinpointed by British and Russian scientists. Lake Vostok, as it is called, was first detected in the 1970s using radio-echo signals received on an orbiting satellite and has now been mapped with much greater accuracy. The equivalent of Lake Ontario in size and as deep as 500 m in places, this body of fresh water is warmed from below by the heat of the Earth and insulated above from the Antarctic chill by a 4-km-thick roof of ice. A drilling team near the Russian Vostok Station (studying layers in the ice sheet) would have broken through to the sub-glacial lake, but operations have been halted for fear of contaminating the water, which might harbor unique bacteria. Methods for analyzing the ultra-pure, ancient water are being pondered. (A.P. Kapitsa et al., Nature 20 June 1996.)