论文标题
拟议的能量代谢无法解释金星的大气化学
Proposed energy-metabolisms cannot explain the atmospheric chemistry of Venus
论文作者
论文摘要
金星云中的生命，如果以足够高的丰度存在，则必须影响大气化学。有人提出，丰富的金星寿命可以使用三种可能的硫能量代谢从其环境中获得能量。这些新陈代谢提高了金星的神秘云层的可能性，因此$ _2 $ depletion是由生命引起的。在这里，我们夫妇分别提出了能量 - 代谢，并在光化学 - 金属学代码中，并在生命产生观察到的$ _2 $ depletion的情况下，自言自语地预测金星大气的组成。使用这种光生化学动力学代码，我们表明所有三种新陈代谢都可以产生$ _2 $ depletions，但要通过违反对金星大气化学的其他观察性约束来做到这一点。在违反观察性约束之前，我们计算云中硫化生物寿命的最大可能的生物量密度为$ \ sim10^{ - 5} \， - \， - \，10^{ - 3} \，{\ rm mg \ rm mg \，m^，m^{ - 3}} $。所采用的方法同样适用于金星样系外行星上的空中生物圈，这些行星在不久的将来最适合大气表征的行星。
Life in the clouds of Venus, if present in sufficiently high abundance, must be affecting the atmospheric chemistry. It has been proposed that abundant Venusian life could obtain energy from its environment using three possible sulfur energy-metabolisms. These metabolisms raise the possibility of Venus's enigmatic cloud-layer SO$_2$-depletion being caused by life. We here couple each proposed energy-metabolism to a photochemical-kinetics code and self-consistently predict the composition of Venus's atmosphere under the scenario that life produces the observed SO$_2$-depletion. Using this photo-bio-chemical kinetics code, we show that all three metabolisms can produce SO$_2$-depletions, but do so by violating other observational constraints on Venus's atmospheric chemistry. We calculate the maximum possible biomass density of sulfur-metabolising life in the clouds, before violating observational constraints, to be $\sim10^{-5}\,-\,10^{-3}\,{\rm mg\,m^{-3}}$. The methods employed are equally applicable to aerial biospheres on Venus-like exoplanets, planets that are optimally poised for atmospheric characterisation in the near future.
