Lake Vostok lies four kilometers beneath the ice sheet of Antarctica underneath Russia’s Vostok Station. It is the largest of 145 lakes that have been discovered beneath the ice sheet, approximately the size of Lake Ontario. Because of the massive pressure, it is possible for the water to remain in liquid form. It is constantly melting and refreezing as the ice sheet moves across the lake. A unique ecosystem could very possibly survive in the extreme conditions of the lake. If so, it would be a major scientific discovery, as analogous environments exist elsewhere in our solar system. We may find out soon, as a Russian team continues to work drilling down towards the lake.