A photo with the subtitle “postcard from the edge of space” appeared in the official NASA profile. It captures an unusual atmospheric phenomenon.

The photo with silver-blue clouds was taken from the International space station. In the description of the frame, NASA representatives explain that these clouds are “visible only when the Sun is below the earth’s horizon and illuminates them.” It also adds that the photo was taken at an altitude of about 430 kilometers above the South Pacific Ocean.

Recall that silvery clouds are the highest in the earth’s atmosphere. They form in the mesosphere at an altitude of about 85 km and are only visible when illuminated by the Sun, when it is at an altitude of 6-16° below the horizon, while the lower layers of the atmosphere are in the earth’s shadow.