Antarctica's Icebound Lake Unter-See Nurtures Ancient-Style Stromatolites

NASA's Earth Observatory highlights Lake Unter-See in Antarctica, a deep, permanently ice-covered lake with unusually high dissolved oxygen, low CO2, and alkaline water that hosts tall conical stromatolites formed by cyanobacteria. These modern microbial reefs resemble Earth's earliest fossils and offer clues about life on icy worlds; a 2019 glacial flood increased water levels by about 2 meters, releasing 17.5 million cubic meters of meltwater and altering the lake's chemistry.