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Lake Vida is a hypersaline lake in Victoria Valley, the northernmost of the large McMurdo Dry Valleys, on the continent of Antarctica. It is isolated under year-round ice cover, and is considerably more saline than seawater. It came to public attention in 2002 when microbes frozen in its ice cover for more than 2,800 years were successfully thawed and reanimated. ==Introduction== Lake Vida is one of the largest lakes in the McMurdo Dry Valley region and is a closed-basin endorheic lake. The permanent surface ice on the lake is the thickest non-glacial ice on earth, reaching a depth of at least . The ice at depth is saturated with brine that is seven times as saline as seawater. The high salinity allows the brine to remain liquid at an average yearly water temperature of . The ice cap has sealed the saline brine from external air and water for thousands of years creating a time capsule for ancient DNA. This combination of lake features make Lake Vida a unique lacustrine ecosystem on Earth.〔(Annika Mosier ) at Desert Research Institute〕 The lake gained widespread recognition in December 2002 when a research team, led by the University of Illinois at Chicago's Peter Doran, announced the discovery of 2,800‑year‑old halophile microbes (primarily filamentous cyanobacteria) preserved in ice layer core samples drilled in 1996.〔National Science Foundation (press release ) for Doran ''et al.'' (2003)〕 The microbes reanimated upon thawing, grew and reproduced. Due to this discovery and the freezing mechanisms forming Lake Vida's ice-seal, Lake Vida is now noted as a location for research into Earth's climate and life under extreme conditions, specifically the fauna that could have existed on Mars. The unmanned Lake Vida Meteorological Station monitors climate conditions around the lake year round for such scientific study.〔(Lake Vida Meteorology Station )〕〔(360° Panorama ) from Lake Vida Meteorologic Station〕 A 2010 field campaign, funded by the National Science Foundation through the American Recovery and Reinvestment Act of 2009, to investigate the microbiology and geochemistry of Lake Vida. Led by Peter Doran and Alison Murray from Nevada's Desert Research Institute, the expedition recovered ice cores, brine and sediment samples from the lake using clean drilling procedures to avoid contamination.〔(【引用サイトリンク】date=September 14, 2009 )〕 The lake itself has no permanent settlements or infrastructure. The nearby Lake Vida Meteorological Station is unmanned, sending meteorological data to McMurdo Dry Valleys Long Term Ecological Research organization. The closest human settlement is Scott Base McMurdo approximately away.〔(Contaminents in Freezing Ground ), Sanpe et al.〕 In addition to the unmanned observation station, a 5-day emergency supply of food for 6 people is cached from the southwestern shore.〔(NASA Quest ), the Lake Vida cache〕 Research teams establish temporary camps from which research activities are conducted on short term basis in the summer months. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Lake Vida」の詳細全文を読む スポンサード リンク
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