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.

Surprisingly, perhaps, the sun is brightest in the blue and green parts of the spectrum and dims toward the red. Naively, you might think this means the sun is teal! But it’s clearly not.

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 ...