For centuries people on earth have been wondering what is the airglow that happens in the night sky to appear so brighter after the dusk, and even without the moon on some special nights.
The night or day is not special, and the sky looks special when it stays so illuminated and bright even at complete nightfall, and looks strangely mysterious and lovely. Scientists have been studying the phenomenon which is not rare, and yet not too frequent.
What is airglow
Oxygen molecules in the atmosphere break into ions when they receive the UV radiations from the sun and other cosmic rays. These ions float in the air, and again try to combine with other ions to form molecules. In the process, the numerous reactions that occur generate enough energy to get converted into the light or aura, which then gets visible in the night sky.
This reaction is not bound to happen at night only. It can happen anytime after turbulence in weather, or a storm etc. But the results are visible only at night when the luminous celestial bodies dominating the near sky do not show.
Airglow is an excellent phenomenon that has been questioned about, researched a lot, and studied for centuries. Finally, scientists have an answer now.
How to watch airglow
You really can watch airglow from the earth when the sky is out of disturbances, light pollution from the earth, and the phenomenon is happening. It doesn’t show often, yet it happens almost 7% of the times at different places of the earth and can be seen from parts of the globe. You have to be lucky to find a disturbance-free sky on the night of airglow to see the aura illuminate the dark sky.
From a space station or satellite also it’s visible when it happens. It’s visible as a thin green aura or cloud above the earth at some places.
Do not confuse it with aurora borealis
Airglow is a different phenomenon and aurora borealis is different. They are not to be confused. Airglow can happen at any place on earth, and aurora happens only near the poles. The colors seen in Aurora are distinct shades and diffused light streaks, but Airglow is just the strangely bright sky at night which should ideally be dark otherwise.