They look almost more like abstract art, geological formations or perhaps space phenomena, but these incredible images from the International Space Station by Don Petit of NASA depict some of the densest urban areas on Earth – such as Tokyo, pictured above and shot at night.
London burns brightly in the middle, surrounded by suburban dots that radiate out from its glowing core – clearly the hub for as far as the eye (or wide-angle space-station lens) can see.
The Las Vegas strip is said to be the brightest place on the planet as seen from space, and this image indeed does it justice – the central lights seem to almost burn through the black of the photo.
Chicago can be seen spreading out in all directions except into the black void of Lake Michigan bordering the city to the East.
Speaking of sprawl, Sao Paolo in Brazil is an amazing example of unchecked organic urban growth, slowly crawling out from an ill-defined center to light up the darkness all around it.