LEXEN/ SGER: The LAREDO Sampler: Novel Equipment for Experimentation at High Temperature and Pressure on the Seafloor

地球地下生物圈的概念最近引起了全世界研究人员和公众的想象。与深海热液喷口有关的热的地下生物圈的证据包括对最近喷发地点出现的絮状微生物物质进行的潜水观测，以及在扩散（冷）热液中发现超嗜热菌，鉴于其热生长要求，这些微生物一定起源于地下更深（更热）的区域。海底活跃的硫化物结构或黑烟囱释放出高温流体，据推测这些流体是冲刷过这种地下生境的，这提供了一个机会，可以测试地球上地下生物圈的上部热边界，并通过外推法测试宇宙中的其他地方。该提案旨在完成一种称为拉雷多取样器的新型原位钛装置的开发和潜水测试阶段，该装置可部署在黑色simoker的聚焦流中，在没有减压效应的情况下在高温下进行原位微生物实验。同样的或相继的模型还可用于在静水压力下对有机化合物的热稳定性或对评估生命起源于海底以下的可能性至关重要的其他非生物过程进行现场测试。一个（未来的）流线型版本的采样器，可部署在热油井或大洋钻探计划的遗留孔深处，可用于将地理测试范围扩展到陆地和非喷口地点。最近人们对地下生物圈、极端环境中的生命以及天体生物学这一新领域的兴趣激增，这表明，着手开发有效的、即使风险很高的深海实验工具的时机已经成熟，这些工具可以提供在实验室模拟中无法获得的新信息。

The concept of a subsurface biosphere on Earth has recently captured the imagination of researchers and the public worldwide. Evidence for a hot subsurface biosphere associated with deep sea hydrothermal vents includes submersible observations of flocculent microbial material emerging from recent eruption sites and the detection of hyperthermophiles in diffuse (cool) hydrothermal fluids, microorganisms that must have originated in deeper (hotter) realms of the subsurface given their thermal growth requirements. Active sulfide structures or black smokers on the seafloor, releasing high temperature fluids that have presumably flushed through such subsurface habitats, provide an opportunity to test for the upper thermal boundaries of the subsurface biosphere on Earth and, by extrapolation, elsewhere in the Universe. This proposal is to complete the development and submersible testing phase of a novel in situ titanium device, called the LAREDO sampler, that can be deployed in the focused flow of a black simoker for insitu microbial experimentation at high temperature in the absence of decompression effects. The same or successive models can also provide for in situ tests of the thermal stability of organic compounds under hydrostatic pressure or of other abiotic processes critical to assessing the possibility that life may have originated in the subseafloor. A (future) streamlined version of the sampler, deployable deep within a hot oil well or a legacy hole of the Ocean Drilling Program, could be used to extend the geographic testing range to terrestrial and non vent sites. The recent explosion of interest in the subsurface biosphere, in life in extreme environments, and in the new field of astrobiology, suggests that the time is ripe to proceed with development of effective, if high risk, deep sea experimental tools that can provide novel information not obtainable in laboratory simulations.