Flying over East Asia, astronauts on the International Space Station (ISS) took this night image of the Korean Peninsula. Unlike daylight images, city lights at night illustrate dramatically the relative economic importance of cities, as gauged by 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. There are 25.6 million people in the Seoul metropolitan area—more than half of South Korea’s citizens—while Gunsan’s population is 280,000.
North Korea is almost completely dark compared to neighboring South Korea and China. The darkened land appears as if it were a patch of water joining the Yellow Sea to the Sea of Japan. Its capital city, Pyongyang, appears like a small island, despite a population of 3.26 million (as of 2008). The light emission from Pyongyang is equivalent to the smaller towns in South Korea.
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.
Astronaut photograph ISS038-E-38300 was acquired on January 30, 2014, with a Nikon D3S digital camera using a 24 millimeter lens, and is provided by the ISS Crew Earth Observations Facility and the Earth Science and Remote Sensing Unit, Johnson Space Center. The image was taken by the Expedition 38 crew. It has been cropped and enhanced to improve contrast, and lens artifacts have been removed. The International Space Station Program supports the laboratory as part of the ISS National Lab to help astronauts take pictures of Earth that will be of the greatest value to scientists and the public, and to make those images freely available on the Internet. Additional images taken by astronauts and cosmonauts can be viewed at the NASA/JSC Gateway to Astronaut Photography of Earth. Caption by M. Justin Wilkinson, Jacobs at NASA-JSC.
The city of Seoul (originally known as Hanyang) has been the capital of Korea for more than 600 years. This astronaut photograph illustrates the Seoul urban area at night. Major roadways and river courses (such as the Han River) are clearly outlined by street lights, while the brightest lights indicate the downtown urban core (center of image) and large industrial complexes. One such complex is located at the far left of the image and occupies an island in the Yellow Sea. Very dark regions in the image are mountains or large bodies of water. Nighttime images have been used extensively in urban climate and urban growth research to map the extent of urban (bright) versus rural (dark) regions.