论文标题：Mineral dust increases the habitability of terrestrial planets but confounds biomarker detection

期刊：Nature Communications

作者：Ian A. Boutle, Manoj Joshi et.al

发表时间：2020/06/09

数字识别码：10.1038/s41467-020-16543-8

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根据本周《自然-通讯》发表的一项研究Mineral dust increases the habitability of terrestrial planets but confounds biomarker detection，大气矿尘或许会提高系外行星的潜在宜居性。这项发现表明在研究类地系外行星时，需要考虑矿尘的潜在影响。

所谓“宜居带”，指的是恒星周围存在一个表面可能有液态水的类地行星的区域。因此，它是搜索地外生命的重点目标。但是，宜居性也取决于行星大气的组成。矿尘（行星表面的碳-硅酸盐物质）可能影响气候系统，但是在此之前，在构建系外行星的气候模型时一直被忽略了。

英国英国气象局的Ian Boutle及同事通过模拟方式，揭示了大气矿尘如何对类地系外行星的宜居性产生重大影响。他们发现在潮汐锁定的行星上（始终以同一面朝向恒星），矿尘会使行星的阳面降温，使阴面升温，从而扩大了这类行星的宜居带范围。他们认为矿尘可以减缓宜居带内缘的行星的水流失，并温暖宜居带外缘的行星。

矿尘对行星气候的影响的概述。

credit: Boutle et al.

通过模拟系外行星的透射光谱，作者还发现矿尘会模糊关键生物标志物（如水蒸气和氧气）的存在，因此在解读有关系外行星宜居性的观测结果时，应将这一点考虑在内。

摘要：Identification of habitable planets beyond our solar system is a key goal of current and future space missions. Yet habitability depends not only on the stellar irradiance, but equally on constituent parts of the planetary atmosphere. Here we show, for the first time, that radiatively active mineral dust will have a significant impact on the habitability of Earth-like exoplanets. On tidally-locked planets, dust cools the day-side and warms the night-side, significantly widening the habitable zone. Independent of orbital configuration, we suggest that airborne dust can postpone planetary water loss at the inner edge of the habitable zone, through a feedback involving decreasing ocean coverage and increased dust loading. The inclusion of dust significantly obscures key biomarker gases (e.g. ozone, methane) in simulated transmission spectra, implying an important influence on the interpretation of observations. We demonstrate that future observational and theoretical studies of terrestrial exoplanets must consider the effect of dust.

（来源：科学网）