An astronaut's photos of a strange 'night-shining cloud' above French Polynesia has won plaudits back on Earth.
The picture captures the ethereal, luminescent clouds from the unique perspective of the International Space Station.
It was taken on 5 January 2013, and Nasa explains that it depicts clouds between 76 to 85 kilometers above the Earth's surface, near the boundary of the mesosphere and thermosphere, known as the mesopause.
The clouds are formed when water vapour freezes into ice crystals, which are high enough to still be illuminated when the sun is below the horizon from the ground.
As a result they 'shine' after sunset, giving the sky a strange glow.
Unusually for the ISS, this image was taken with a long lens which allowed for greater detail.
"Below the brightly-lit noctilucent clouds, across the center of the image, the pale orange band is the stratosphere," Nasa said.