A new photograph, which was taken on board the International Space Station (ISS) captures the beauty of one of the rarest of cloud formations – Noctilucent clouds. ESA Astronaut Tim Peake, who is currently on board the ISS, snapped a photo of these “polar mesospheric”, or “Noctilucent” or “night shining” clouds that sit on the edge of the atmosphere.

The clouds, the existence of which were only formally recorded in 1885, are rare, form at a high altitude in the atmosphere, usually between 76 to 85 kilometers (47 to 53 miles) above the Earth’s surface in a region known as the mesopause (which is near the boundary of the mesosphere and thermosphere).

At these altitudes, water vapor can freeze into clouds of ice crystals. When the sun is below the horizon and the ground is in darkness, these high clouds may still be illuminated, lending them their ethereal, “night shining” qualities.

Unlike our rainy clouds that sit around 10,000-30,000 feet (or lower), these clouds sit 50 miles high in space.

We’re seeing some rare high altitude noctilucent clouds just now – hope for some better pics next week pic.twitter.com/xzHMEyJ9Mk

— Tim Peake (@astro_timpeake) June 2, 2016

These unusual clouds are known to form above the earth’s polar regions. As the lower atmosphere warms, the upper atmosphere gets cooler, and ice crystals form on meteor dust and other particles high in the sky. The result is noctilucent or “night-shining” clouds — electric blue wisps that grow on the edge of space, according to NASA.

Scientists are still working to fully understand the formation of such clouds with differing views on their increasing presence could indicate, if anything, with some believing they are “potential indicators” of atmospheric changes resulting from an increase in greenhouse gases.