The population of Riyadh, the capital city of Saudi Arabia, has risen dramatically in the last half century—from 150,000 in 1960 to 5.4 million in 2012. The city appears as a brightly colored patchwork in this nighttime astronaut photograph. The brightest lights, apart from those on the old Riyadh Airbase, follow the commercial districts along King Abdullah Road and King Fahd Branch Road. Many of the darker patches within the built area are city parks.
University sectors stand out with different street and light patterns, including the King Saud University campus—which houses the Arabic Language Institute—and the Princess Nora Bint Abdul Rahman University—which is the largest all-female university in the world. Highways and various ring roads also stand out due to bright, regular lighting. Lighted developments beyond the ring roads mark the growth of the city (image lower left and lower right). Newer neighborhoods, set further from the city center, are recognizable by blue-gray lightning. By contrast with night images, detail within the urban area is far less distinct in daylight images such as this one.
Astronaut photograph ISS033-E-20288 was acquired on November 13, 2012, with a Nikon D3S digital camera using a 400 millimeter lens, and is provided by the ISS Crew Earth Observations experiment and Image Science & Analysis Laboratory, Johnson Space Center. 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/ESCG at NASA-JSC. Image Credit: NASA/USGS EROS Data Center.