Why Can We See a Yellow Glow Surrounding the Earth In Space

You can see this yellow layer in the atmosphere in images taken from space, it's quite easy to catch when the skies are dark and the camera exposures are long enough. The glow comes from atomic sodium being excited and then re-emitting light in the 589 nanometer range, it's a colour we're familiar with becuase low pressure sodium lights are still commonly used for street lighting due to Sodium's efficiency.

Видео Why Can We See a Yellow Glow Surrounding the Earth In Space канала Scott Manley