Originally Answered: Does the atmosphere of Mars contain oxygen?
The Five Most Abundant Gases in the Martian Atmosphere
Surface is highly oxygenated, as you can see by the red colour, iron oxides. Salts in form of perchlorates, chlorates and sulfates instead of chlorides and sulfides, so they are far more oxygenated than the corresponding salts on Earth.
Mars may have had a more oxygen rich atmosphere long ago - but generated by photodissociation of water - this may be partly why it lost its water - that some of it ended up as oxygen - because Mars has no magnetic field to protect from cosmic radiation and the ionizing radiation splitting the water molecules apart.
But - that's just a theory, not proven. MAVEN will find out more.
Mars Had Oxygen-Rich Atmosphere 4 Billion Years Ago, Shows New Study
About the Author
Robert Walker
Writer of articles on Mars and Space issues - Software Developer of Tune Smithy, Bounce Metronome etc.Studied at Wolfson College, Oxford
Lives in Isle of Mull
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