North Korea, a land of darkness: Nasa video

Astronauts on the International Space Station have taken a night image of the Korean Peninsula.

Video from Manuel Dorne

According to Nasa, lights at night illustrate the economic importance of cities as gauged by their relative size.

"In this north-looking view, it is immediately obvious that greater Seoul is a major city and that the port of Gunsan is minor by comparison," Nasa said in a statement.

North Korea meanwhile looks almost "as if it were a patch of water joining the Yellow Sea to the Sea of Japan," with its capital Pyongyang looking like a small island.

"Coastlines are often very apparent in night imagery, as shown by South Korea’s eastern shoreline. But the coast of North Korea is difficult to detect. These differences are illustrated in per capita power consumption in the two countries, with South Korea at 10,162 kilowatt hours and North Korea at 739 kilowatt hours," Nasa said.