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  2. Atmosphere of Earth - Wikipedia

    en.wikipedia.org/wiki/Atmosphere_of_Earth

    Air also contains a variable amount of water vapor, on average around 1% at sea level, and 0.4% over the entire atmosphere. Earth's early atmosphere consisted of accreted gases from the solar nebula, but the atmosphere changed significantly over time, affected by many factors such as volcanism, impact events, weathering and the evolution of ...

  3. Paleoatmosphere - Wikipedia

    en.wikipedia.org/wiki/Paleoatmosphere

    A paleoatmosphere (or palaeoatmosphere) is an atmosphere, particularly that of Earth, at some unspecified time in the geological past.. When regarding geological history of Earth, the paleoatmosphere can be chronologically divided into the Hadean first atmosphere, which resembled the compositions of the solar nebula; the Archean second atmosphere (also known as the prebiotic atmosphere), which ...

  4. Great Oxidation Event - Wikipedia

    en.wikipedia.org/wiki/Great_Oxidation_Event

    The Great Oxidation Event (GOE) or Great Oxygenation Event, also called the Oxygen Catastrophe, Oxygen Revolution, Oxygen Crisis or Oxygen Holocaust, [2] was a time interval during the Earth's Paleoproterozoic era when the Earth's atmosphere and shallow seas first experienced a rise in the concentration of free oxygen. [3]

  5. All Life on Earth Might Have Started From Lightning ... - AOL

    www.aol.com/lifestyle/life-earth-might-started...

    This is extremely important, as Earth’s early atmosphere would’ve been made up of nonreactive N 2 molecules. Lightning was the essential piece needed to create the ingredients essential for ...

  6. Paleoclimatology - Wikipedia

    en.wikipedia.org/wiki/Paleoclimatology

    About 3.4 billion years ago, nitrogen was the major part of the then stable "second atmosphere". An influence of life has to be taken into account rather soon in the history of the atmosphere because hints of early life forms have been dated to as early as 3.5 to 4.3 billion years ago. [21]

  7. Geological history of oxygen - Wikipedia

    en.wikipedia.org/wiki/Geological_history_of_oxygen

    Photosynthetic prokaryotic organisms that produced O 2 as a byproduct lived long before the first build-up of free oxygen in the atmosphere, [5] perhaps as early as 3.5 billion years ago. The oxygen cyanobacteria produced would have been rapidly removed from the oceans by weathering of reducing minerals, [ citation needed ] most notably ferrous ...

  8. History of Earth - Wikipedia

    en.wikipedia.org/wiki/History_of_Earth

    The atmosphere is nebular. Possible early oceans or bodies of liquid water. The Moon is formed around this time probably due to a protoplanet's collision into Earth. Archean: 4,000–2,500 Prokaryote life, the first form of life, emerges at the very beginning of this eon, in a process known as abiogenesis.

  9. Prebiotic atmosphere - Wikipedia

    en.wikipedia.org/wiki/Prebiotic_atmosphere

    The modern atmosphere is oxidizing, due to the large volume of atmospheric O 2. In an oxidizing atmosphere, the majority of atoms that form atmospheric compounds (e.g. C) will be in an oxidized form (e.g. CO 2) instead of a reduced form (e.g. CH 4). In a reducing atmosphere, more species will be in their reduced, generally hydrogen-bearing forms.