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  2. Oxygen - Wikipedia

    en.wikipedia.org/wiki/Oxygen

    Oxygen gas is the second most common component of the Earth's atmosphere, taking up 20.8% of its volume and 23.1% of its mass (some 10 15 tonnes). [19] [70] [d] Earth is unusual among the planets of the Solar System in having such a high concentration of oxygen gas in its atmosphere: Mars (with 0.1% O 2 by volume) and Venus have much less. The O

  3. Abundance of elements in Earth's crust - Wikipedia

    en.wikipedia.org/wiki/Abundance_of_elements_in...

    The Earth's crust is one "reservoir" for measurements of abundance. A reservoir is any large body to be studied as unit, like the ocean, atmosphere, mantle or crust. Different reservoirs may have different relative amounts of each element due to different chemical or mechanical processes involved in the creation of the reservoir. [1]: 18

  4. Abundance of the chemical elements - Wikipedia

    en.wikipedia.org/wiki/Abundance_of_the_chemical...

    The abundance of the chemical elements is a measure of the occurrences of the chemical elements relative to all other elements in a given environment. Abundance is measured in one of three ways: by mass fraction (in commercial contexts often called weight fraction), by mole fraction (fraction of atoms by numerical count, or sometimes fraction of molecules in gases), or by volume fraction.

  5. Geological history of oxygen - Wikipedia

    en.wikipedia.org/wiki/Geological_history_of_oxygen

    Stages 4 and 5 (0.85 Ga–present): O 2 sinks filled, the gas accumulates. [1] Although oxygen is the most abundant element in Earth's crust, due to its high reactivity it mostly exists in compound forms such as water, carbon dioxide, iron oxides and silicates.

  6. Helium - Wikipedia

    en.wikipedia.org/wiki/Helium

    Although it is rare on Earth, helium is the second most abundant element in the known Universe, constituting 23% of its baryonic mass. Only hydrogen is more abundant. [28] The vast majority of helium was formed by Big Bang nucleosynthesis one to three minutes after the Big Bang. As such, measurements of its abundance contribute to cosmological ...

  7. Trace gas - Wikipedia

    en.wikipedia.org/wiki/Trace_gas

    The second most important greenhouse gas, and the most important trace gas affected by man-made sources, is carbon dioxide. [12] It contributes about 20% of Earth's total greenhouse effect. [13] The reason that greenhouse gases can absorb infrared radiation is their molecular structure.

  8. Scientists propose warming up Mars by using heat-trapping ...

    www.aol.com/news/scientists-propose-warming-mars...

    The scientists proposed continuously releasing tiny rod-shaped particles - nanorods - into the atmosphere at a rate of about eight gallons (30 liters) per second for years.

  9. Argon - Wikipedia

    en.wikipedia.org/wiki/Argon

    Argon is the most abundant noble gas in Earth's crust, comprising 0.00015% of the crust. Nearly all argon in Earth's atmosphere is radiogenic argon-40, derived from the decay of potassium-40 in Earth's crust. In the universe, argon-36 is by far the most common argon isotope, as it is the most easily produced by stellar nucleosynthesis in ...