According to gadget360:

Atomic oxygen - an elemental form of oxygen that does not exist in Earth's atmosphere - affects how other gases escape Mars and therefore has a significant impact on the planet's atmosphere.
An instrument onboard the Stratospheric Observatory for Infrared Astronomy (SOFIA) - a joint project of Nasa and the German Aerospace Center - helped detect these atoms in the upper layers of the Martian atmosphere known as the mesosphere, Nasa said in a statement.




"Atomic oxygen in the Martian atmosphere is notoriously difficult to measure," said SOFIA project scientist Pamela Marcum.

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