ISS captures ‘rare’ sighting of noctilucent clouds (PHOTO)

A new image taken on board the International Space Station captures the beauty of one of the rarest of cloud formations – noctilucent clouds.

Photographed by British astronaut Tim Peake, the picture shows the beautiful blue tint of what are known as polar mesospheric clouds, or more commonly as noctilucent or "night shining" clouds.

The clouds, the existence of which were only formally recorded in 1885, form at a high altitude in the atmosphere, usually around 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.

The clouds are known to form above the earth’s polar regions and are caused by the lower atmosphere warming up while the upper atmosphere cools, with ice crystals then forming on meteor dust and other particles high in the sky.

Usually only seen at twilight with the sun below the horizon, some of its light continues to illuminate the clouds to create "electric blue wisps that grow on the edge of space," according to NASA.

You don’t need to be an astronaut to see such unusual cloud formations though, with night shining clouds also visible from here on earth.

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. (RT)