Abstract

The Earth’s N₂-dominated atmosphere is a very special feature. Firstly, N₂ as main gas is unique on terrestrial planets in the inner Solar System and gives a hint for tectonic activity. Studying the origins of atmospheric nitrogen and its stability provides insights into the uniqueness of the Earth’s habitat. Secondly, the coexistence of N₂ and O₂ within an atmosphere is unequaled in the entire Solar System. Such a combination is strongly linked to the existence of aerobic lifeforms. The availability of nitrogen on the surface, in the ocean, and within the atmosphere can enable or prevent the habitability of a terrestrial planet, since nitrogen is vitally required by all known lifeforms. In the present work, the different origins of atmospheric nitrogen, the stability of nitrogen dominated atmospheres, and the development of early Earth’s atmospheric N₂ are discussed. We show why N₂–O₂ atmospheres constitute a biomarker not only for any lifeforms but for a-erobic lifeforms, which were the first major step that led to highly developed life on Earth.

中文翻译：

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生命是存在N 2 -O 2主导气氛的唯一原因

摘要

地球的N ₂为主的大气层是一个非常特殊的特征。首先，N ₂作为主要气体在太阳系内部的地球行星上是独特的，并为构造活动提供了提示。研究大气氮的起源及其稳定性可以提供对地球栖息地独特性的见解。其次，N ₂和O ₂共存在整个太阳系中，大气中的空气是无与伦比的。这种组合与有氧生命形式的存在紧密相关。由于所有已知生命形式都极其需要氮，因此在表面，海洋和大气中可获得的氮可以启用或阻止地球行星的可居住性。在本工作中，讨论了大气氮的不同起源，氮占主导的大气的稳定性以及地球早期大气N ₂的发展。我们证明了为什么N ₂ -O ₂气氛不仅对任何生命形式而且对于有氧生命形式都构成生物标记，这是导致地球高度发达的生命的第一步。