Buy the Earth at Night North America photo. High quality space picture, slide, or Duratrans backlit transparency. NASA photograph PIA02991-NA. Wide variety of sizes. This image of North America'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. Cities tend to grow along coastlines and transportation networks. The United States interstate highway system appears as a lattice connecting the brighter dots of city centers. Credit: Image by Craig Mayhew and Robert Simmon, NASA GSFC, based on DMSP data courtesy Christopher Elvidge, NOAA National Geophysical Data Center. |