Cities from Space
by Michael E. Marotta
To an observer in space, humanity’s footprints on the surface of the Earth are large and varied. They include the regular patterns of irrigated cropland, straight lines of roads and railways running across continents, reservoirs on river systems, and the cement rectangles of ports and seawalls along coastlines. But what about humanity’s signature footprint—cities? By day, cities viewed from space can blend into the countryside, or appear as gray smudges, depending on the style of development and size of the urban area.
At night however, city lights present the space observer spectacular evidence of our existence, our distribution, and our ability to change our environment
http://earthobservatory.nasa.gov/Features/CitiesAtNight/
The Registered Cities List is a complete list of the images of cities that are registered, or geometrically corrected, and tweaked to match a map of the cities with even scale.
http://eol.jsc.nasa.gov/cities/list.htm
The research presented here is primarily focused on the physical properties of a wide range of urban environments using passive measurement of optical reflectance and thermal emission as well as optical emission of nighttime lights.
Short wavelength
Near Infrared
Visible Radiance
Comparative analyses of urban reflectance (visible and infrared color) and surface temperature allow us to develop robust criteria for distinguishing urban land cover from non-anthropogenic land covers.
http://sedac.ciesin.columbia.edu/ulandsat/
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