A unique perspective of rare clouds as the sun shines through a layer of luminous noctilucent clouds captured from the International Space Station (ISS).

Astronaut Alexander Gerst took a picture in a class of its own during his stay on the ISS. It shows an orbital sunrise, through a layer of luminous noctilucent clouds, highlighting how high these stunning clouds actually are.

These are at the upper edge of the blue area. It is impossible not to notice how high the luminous noctilucent clouds actually are compared to “normal clouds”. At an altitude of 80 to 85 kilometres, they only form when temperatures are particularly low due to strong turbulence in this altitudinal layer of the atmosphere.

From Earth, the silky threads of the glowing noctilucent clouds can only be observed during the solar zenith, i.e. from mid-May to the end of July.

The sun must be below the horizon during this time. This is because the clouds are so thin that the sun far outshines their magical light during the day.

If you manage to spot their rare appearance, be sure to capture the moment, we would love to see what you spot! Send in pictures by tapping the image icon in the corner of the app or using our uploader.