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温泉具有很重要的天体生物学研究意义,在地球上许多远古生物都生存在热水温泉周围。如果生命形式真得存在于火星,温泉沉积物将是寻找有机生命物理或化学证据的理想地点,它将成为未来勘测任务的重点目标之一。
美国宇航局约翰逊航天中心天体材料研究和探测科学理事会的Carlton C.Allen和DorothyZ.Oehler指出,从火星侦察轨道器上“高清晰科学实验成像仪器”(HiRISE)所获得的最新图像数据暗示弗纳尔环形山的温泉沉积层可能在远古时期具有有机生命活动性。此外,相关的数据还显示弗纳尔环形山南部曾有液态水从地下流至火星表面,在这里很有可能形成火星生命体。
美国波特兰大学地质系副教授、《天体生物学》杂志编辑的SherryL.Cady说:“温泉沉积层将是未来火星勘测任务中的重点目标!”他还指出,像地球上的远古温泉沉积层中保存着微生物群体的化石迹象,在温泉附近的立体空间环境中存在着许多生物群体。对温泉沉积层的分析研究将有助于揭示早期生命体的生物组织、微生物残骸、矿物质中化学化石等证据,温泉液体中较典型地含有可溶解性矿物质离子,当它们沉积下来并形成热液沉积物时,将显现出各种类型的生物学迹象。
ASTROBIOLOGY Volume 8, Number 6, 2008. Mary Ann Liebert, Inc. DOI: 10.1089/ast.2008.0239
A Case for Ancient Springs in Arabia Terra, Mars
Carlton C. Allen1 and Dorothy Z. Oehler1
Abstract
Based on new image data from the High Resolution Imaging Science Experiment (HiRISE) on Mars Reconnaissance Orbiter (MRO), a case can be made that several structures in Vernal Crater, Arabia Terra are ancient
springs. This interpretation is based on comprehensive geomorphologic analysis coupled with assessment of multiple hypotheses. The structures identified extend across several kilometers and are exceptional in that nothing with their detail and scale has been reported from Mars. The deposits are associated with an extensive fracture system that may have facilitated upward flow of warm fluids. Several additional spring-like features occur in Vernal Crater, and it is possible that these are part of a major province of spring activity. Since springs are environments where life could have evolved on Mars, where that life could have found refuge as the climate became colder and drier, and where signatures of that life may be preserved, Vernal Crater may be a site of major astrobiological importance.
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