These bright, criss-crossing lines represent 58,000 commercial flight routes, seen from above. "Not many people will have been in space and looked down at these routes," says Michael Markieta, a geographic information services consultant at Arup, in Toronto, Canada.
The international airports flying to the most destinations (more than 200) are Frankfurt, Atlanta, Paris and Amsterdam. All flight data comes from openflights.org -- a crowdsourced database -- and flights are represented in blue, with colour intensity proportional to flight length. "Cross-continental flights that wrap around the globe are dark blue," Markieta explains. When there are many overlapping trips along the same route, he has increased light exposure, so they are collectively brighter. Markieta drew out each flight path by plotting the latitudes and longitudes of every airport and then using an algorithm called Great Circle, which connects the shortest distance between two points on the Earth's surface.