Airglow over Australia

On October 7, 2018, an astronaut onboard the ISS shot this photograph at an altitude of about 250 miles (400 kilometers) over Australia. In this view, stars appear more numerous along the image center where the plane of the disk-shaped Milky Way galaxy extends into space. The orange colors enveloping Earth are known as airglow—diffuse bands of light that stretch roughly 50 to 400 miles (80 to 645 kilometers) into our atmosphere. This type of airglow is known as chemiluminescence, or nightglow. More than just a pretty light show, airglow reveals some of the workings of the upper reaches of our atmosphere. Studying airglow can help scientists learn about the movement of particles near the interface between Earth and space, including the connections between space weather and Earth weather. Airglow reveals some of the conditions of the upper atmosphere, such as its temperature, shape, and the amounts of different types of gases.

See NASA Earth Observatory