What is the largest subglacial lake in Antarctica?

The largest subglacial lake in Antarctica is Lake Vostok. It lies beneath the East Antarctic Ice Sheet near Russia’s Vostok Station, buried under roughly 4,000 meters of ice.

Lake Vostok is about 250 kilometers long and 50 kilometers wide, with an estimated surface area of approximately 12,500 square kilometers. Its water remains liquid despite the extreme cold because geothermal heat warms the lake from below and the enormous pressure of the overlying ice lowers water’s effective freezing point. The lake is estimated to hold about 5,400 cubic kilometers of water.

Scientists first suspected its existence from seismic and airborne radar surveys. Satellite laser-altimetry data helped confirm the lake in the early 1990s, and its discovery was formally published in the 1990s. In 2012, Russian researchers drilled through the ice into the lake, though contamination concerns made exploration controversial. The isolated environment has also attracted interest because it may offer clues about life in extreme environments—and about icy moons such as Europa and Enceladus.