NASA astronaut Don Pettit has shared a stunning image taken during his seven-month mission aboard the International Space Station (ISS). Captured with a 20-second long exposure, the image captures the upper atmosphere airglow above Earth, the stars of deep space, and a docked SpaceX Dragon capsule. It is one of the most extraordinary images of Earth from space ever captured.

The 20-second exposure reveals Earth’s red glow

Pettit shared the image on social media on Sunday, describing it as “SpaceX Dragon flies among deep space stars and a sea of clouds illuminated by red airglow.” The astronaut explained that the image was captured using his “orbital sidereal drive,” a system he invented that compensates for motion on the space station and keeps the stars fixed.

Airglow, also known as airglow, is a natural but faint light produced in the upper atmosphere by the interaction of sunlight with atoms and molecules. From space, it’s usually seen as a thin, colorful band at the edge of the Earth.

While its color is mostly green, it can also occasionally be red or blue. This light, which persists throughout the day, is only visible at night. Unlike auroras, airglow is not caused by solar storms, but by ongoing atmospheric processes.

The orbital sidereal drive system Pettit uses compensates for the ISS’s motion, keeping the camera focused on the stars. This way, stars remain fixed in the frame during long exposures, allowing them to be clearly imaged without becoming trails of light. This system enables the capture of clarity and depth in astrophotography taken from space.

Don Pettit has previously made headlines for the remarkable images he captured while in orbit. Since his last space mission ended in April, he has continued to share new images captured during the mission. Last week, he released an infrared image of the Grand Canyon in Arizona, describing it as “reminiscent of the surface of Mars.”