Xiaohan Wang was driving near Keluke Lake in Qinghai Province in China, but stopped to snap this lovely image of airglow bands framing the Milky Way.
Why would the sky glow like a giant repeating rainbow? Airglow. Now air glows all of the time, but it is usually hard to see. A disturbance however — like an approaching storm — may cause noticeable rippling in the Earth's atmosphere. These gravity waves are oscillations in air analogous to those created when a rock is thrown in calm water. Red airglow likely originates from OH molecules about 87-kilometers high, excited by ultraviolet light from the Sun, while orange and green airglow is likely caused by sodium and oxygen atoms slightly higher up.
Below is a lovely timelapse of airglow above the Roque de Los Muchachos Observatory in the Canary Islands: