Lake Vostok or озеро Восток Russian for “Lake East” is the largest of Antarctica’s almost 400 known subglacial lakes at 143 miles (230 km) long, 31 miles (50 km) wide and as much as 500 meters (1,600 feet) deep. Lake Vostok is located beneath Russia’s Vostok Station under the surface of the central East Antarctic Ice Sheet. The lake is named after Vostok Station.

Scientists believe geothermal energy, or heat from the Earth, keeps the temperature of the lake water hovering around 27 degrees Fahrenheit (minus 3 degrees Celsius).

AntarcticLakes

Image courtesy of: Nicolle Rager-Fuller / National Science Foundation