Amazing Images of Earth captured by the European Space Agency and Nasa Satelittes. The image above is of Egypt and shows the population of Egypt living concentrated over the Nile Delta, useful image to discuss populution,
The link below has other images that could be useful
http://www.guardian.co.uk/environment/gallery/2010/dec/06/satellite-eye-on-earth?intcmp=122#/?picture=369407901&index=7
