Red Planet, Green Glow: Light Emission Phenomenon Spotted in Martian Sky
Nightglow, also known as airglow, is essentially an emission of light by a planet’s atmosphere. In Mars’ case, this emission occurs “due to the recombination of oxygen atoms created in the summer atmosphere and transported by winds to high winter latitudes, at altitudes of 40 to 60 km.”
Source: sputnikglobe.com