氩的奇异情况
The Curious Case of Argon
摘要：
在现代宇宙其他地方寻找生命的过程中，我们正在广泛地寻找以下内容：与地球相似的行星-可居住性的物理指标，以及生命的表现-生物特征。生物特征是一种测量参数，很可能是由生物体引起的，无论是大气气体种类还是某些表面特征。因此，搜索的重点是生命系统产生的产物或现象，主要是微生物，因为它们是我们星球上最丰富的，比如甲烷。然而，我们可能需要区分“生物特征”和“生物指标”这两个术语。生物特征是生物体产生的生物产品，而生物指示剂可能是我们所知的生命所必需的任何东西，如水或岩石行星。在这种情况下，氧气是一种双重生物标志物;首先，它是光合作用的副产品，其次，它是复杂生命的标志，因为复杂的高度组织化的生命需要高水平的氧气。可能还有其他这样的生物指示剂。例如，在我们太阳系的类地行星（包括土卫六）的大气成分中，氩是主要成分之一，而且最近被认为是一种“生物”活性气体，表现出器官保护和神经保护特性，特别是在缺氧条件下。在这里，我们提出，岩石行星大气中的氩是高度有组织的生命的生物指示剂，前提是该行星已经被认为是潜在的可居住的：水，大气和一定的年龄允许复杂的生命进化。我们还描述了其可能的检测方法。
英文摘要：
In the modern search for life elsewhere in the Universe, we are broadly looking for the following: the planets similar to Earth - physical indicators of habitability, and the manifestation of life - the biological signatures. A biosignature is a measured parameter that has a high probability of being caused by the living organisms, either atmospheric gas species or some surface features. Therefore, the focus of a search is on a product or phenomena produced by the living systems, mostly by microorganisms as these are the most abundant on our planet like, say, methane. However, we may need to distinguish the terms `biosignature' and `bioindicator'. A biosignature is what living organisms produce - a bioproduct, while a bioindicator may be anything necessary for life as we know it, such as water or a rocky planet. Oxygen in this case is a double biomarker; first, it is a byproduct of oxygenic photosynthesis and, second, it is a signature of a complex life, because complex highly organized life requires high levels of oxygen. It is possible that there are other such bioindicators. For example, in the atmospheric compositions of terrestrial planets in our Solar System (including Titan), argon is one of the major constituents, moreover it was recently acknowledged to be a `biologically' active gas, exhibiting organprotective and neuroprotective properties, especially under hypoxic conditions. Here we propose that argon in the atmosphere of a rocky planet is a bioindicator of a highly organized life, provided that the planet is already deemed potentially habitable: with water, atmosphere, and of a certain age allowing for the complex life to evolve. We also delineate its possible detection methods.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
