Atmospheric Composition
| Average composition of dry atmosphere (mole fractions) | ||
|---|---|---|
| Gas | per NASA |
|
| Nitrogen, N2 | 78.084% | |
| Oxygen, O2 | 20.946% | |
| Argon, Ar | 0.934% | |
| Minor constituents (mole fractions in ppm) | ||
| Carbon Dioxide, CO2 | 383 | |
| Neon, Ne | 18.18 | |
| Helium, He | 5.24 | |
| Methane, CH4 | 1.7 | |
| Krypton, Kr | 1.14 | |
| Hydrogen, H2 | 0.55 | |
| Water | ||
| Water vapour | Highly variable; typically makes up about 1% |
|
Notes: the concentration of CO2 and CH4 vary by season and location. The mean molecular mass of air is 28.97 g/mol.
Read more about this topic: Atmospheric Chemistry
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“Nor has science sufficient humanity, so long as the naturalist overlooks the wonderful congruity which subsists between man and the world; of which he is lord, not because he is the most subtile inhabitant, but because he is its head and heart, and finds something of himself in every great and small thing, in every mountain stratum, in every new law of color, fact of astronomy, or atmospheric influence which observation or analysis lay open.”
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