Tonight, the starry sky glows red and green - a sign that the molecules of the atmosphere are recovering from the bombardment of sun rays.
Airglow can form wave structures in the lower air layers.
The light phenomenon airglow - an air glow - is a thin, luminous layer on the horizon that can have different colors.
Under favorable conditions, the phenomenon can be seen with the naked eye. Airglow occurs because the intense radiation from the sun breaks up air molecules during the day.
When the molecules merge again at night, they emit a faint, often greenish or reddish glow, so that the night sky is never completely black.
Molecules give different colors
Green airglow comes from oxygen at a height of approximately 80 kilometers.
Oxygen produces a faint blue glow at about 95 kilometers, and red light at 200 to 300 kilometers.
Downwards, at a height of 80 to 90 kilometers, molecules of oxygen and hydrogen can also give a red color. Sodium causes yellowish airglow.
This is how you proceed
To see airglow, look for a dark place with a new moon on 7 November. For example, go outside an hour after sunset and you can see the phenomenon all night long.
You usually see Airglow at a height of approximately 20 degrees above the horizon. Because of the slant angle you look through a thicker layer of airglow than when you look straight up.
To photograph airglow, you illuminate your photo for a long time, for example 30 seconds. The camera captures much more light than the eye and also displays colors and structures better.
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