Back to Article List The sky isn’t just blue — airglow makes it green, yellow, and red too The sky looks blue on a sunny day. But at night, we can see the faint glow of its true color.

It’s typically seen as yellow because of how the light is scattered, with air molecules interacting with the blue and violet wavelengths so only the yellow or red ones can reach our eyes.

So the sky isn’t blue, at least not always. It is a glow-in-the-dark night sky too, coloured a mix of green, yellow and red.

The sky isn’t just blue – airglow makes it green, yellow and red too The distinct colours of airglow are the result of atoms and molecules releasing particular amounts of energy in the form of ...