Atmosphere of Mars

Gas layer surrounding Mars

The atmosphere of Mars is primarily composed of carbon dioxide (95%), molecular nitrogen (2.85%), and argon (2%). It also contains trace levels of water vapor, oxygen, carbon monoxide, hydrogen, and noble gases. The atmosphere of Mars is much thinner and colder than Earth's having a max density 20 g/m³ (about 2% of Earth's value) with a temperature generally below zero down to −60 °C. The average surface pressure is about 610 pascals (0.088 psi) which is 0.6% of the Earth's value.

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