OSXPlanet is a free program currently in beta which "is able to generate live images of the earth as well as other planets in the solar system with additional informations such as the current clouds, storms, satellites, volcanos, earthquakes and times and locations of cities."
The program provides you with real time information from cameras or satellite views and can be set to your location of choice. The program refreshes every minute if you choose and displays as the desktop background.
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