...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Proceedings of the National Academy of Sciences of the United States of America >Atmospheric energy for subsurface life on Mars?
【24h】

Atmospheric energy for subsurface life on Mars?

机译：用于火星地下生命的大气能量？

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The location and density of biologically useful energy sources on Mars will limit the biomass. spatial distribution, and organism size of any biota. Subsurface Martian organisms could be supplied with a large energy flux from the oxidation of photochemically produced atmo- spheric H2 and CO diffusing into the regolith. However, surface abundance measurements of these gases demonstrate that no more than a few percent of this available flux is actually being consumed, suggesting that biological activity driven by atmospheric H_2 and CO is limited in the top few hundred maters of the subsurface. This is significant because the available but unused energy is extremely large: for organisms at 30-m depth. it is 2.000 times previous estimates of hydrothermal and chemical weathering energy and far exceeds the energy derivable from other atmospheric gases. This also implies that the apparent scarcity of life on Mars is not attributable to lack of energy. Instead, the availability of liquid water may be a more important factor limiting biological activity because the photochem- ical energy flux can only penetrate tO 100- to 1.000-m depth. where most H2O is probably frozen. Because both atmospheric and Viking lander soil data provide little evidence for biological activity, the detection of short-lived trace gases will probably be a better indicator of any extant Martian life.
机译：火星上生物学上有用的能源的位置和密度将限制生物量。空间分布以及任何生物群的生物体大小。通过光化学产生的大气H2的氧化和CO扩散到重灰石中，可以为地下火星生物提供大的能量通量。但是，这些气体的表面丰度测量表明，实际消耗的这种可用通量不超过百分之几，这表明由大气中H_2和CO驱动的生物活性在地下的前几百个物质中受到限制。这非常重要，因为可用但未使用的能量非常大：对于30米深的生物。这是以前估计的热液和化学风化能量的2000倍，远远超过了其他大气中产生的能量。这也意味着火星上生命的明显匮乏并不是由于缺乏能量。取而代之的是，液态水的可用性可能是限制生物活性的一个更重要的因素，因为光化学能通量只能穿透100至1.000-m的深度。大多数H2O可能都冻结了。由于大气和维京群岛着陆器的数据都无法提供生物活性的证据，因此，检测短寿命的痕量气体可能会更好地指示任何现存的火星生命。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号