File: Earthlights dmsp.jpg

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Composite image of the Earth at night, created by NASA and NOAA.

NASA Description: This image of Earth’s city lights was created with data from the Defense Meteorological Satellite Program (DMSP) Operational Linescan System (OLS). Originally designed to view clouds by moonlight, the OLS is also used to map the locations of permanent lights on the Earth’s surface.

The brightest areas of the Earth are the most urbanized, but not necessarily the most populated. (Compare western Europe with China and India.) Cities tend to grow along coastlines and transportation networks. Even without the underlying map, the outlines of many continents would still be visible. The United States interstate highway system appears as a lattice connecting the brighter dots of city centers. In Russia, the Trans-Siberian railroad is a thin line stretching from Moscow through the center of Asia to Vladivostok. The Nile River, from the Aswan Dam to the Mediterranean Sea, is another bright thread through an otherwise dark region.

Even more than 100 years after the invention of the electric light, some regions remain thinly populated and unlit. Antarctica is entirely dark. The interior jungles of Africa and South America are mostly dark, but lights are beginning to appear there. Deserts in Africa, Arabia, Australia, Mongolia, and the United States are poorly lit as well (except along the coast), along with the boreal forests of Canada and Russia, and the great mountains of the Himalaya. Also noticeable is the dramatic contrast in light emission between South Korea and North Korea.

Visualization Date: 2000-10-23

[edit] Source A high resolution TIFF image can be found at http://visibleearth.nasa.gov/images/1438/land_lights_16384.tif 16384w x 8192h, 40.6 MB, color (true)

Image description from http://visibleearth.nasa.gov/view_rec.php?id=1438

[edit] Credit Data courtesy Marc Imhoff of NASA GSFC and Christopher Elvidge of NOAA NGDC. Image by Craig Mayhew and Robert Simmon, NASA GSFC.

This image was created by NASA and taken from a NASA website or publication. NASA copyright policy notes that "NASA material is not protected by copyright unless noted". For more information, please refer to the NASA copyright policy page. 
This image is a work of the National Oceanic and Atmospheric Administration, taken or made during the course of an employee's official duties. As works of the U.S. federal government, all NOAA images are in the public domain. 

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